HK1164191B - Irradiation device - Google Patents

Description

Radiation device

Technical Field

The present invention relates to a radiation device for insertion into a bore of the human body to provide photodynamic therapy or diagnosis of diseases, pathologies and conditions thereof.

Background

An example of a pore in the human body where photodynamic therapy is beneficial is the female reproductive tract. Disorders affecting the female reproductive tract are discussed below. Similar conditions or conditions corresponding to similar treatments may occur in other orifices such as the rectum, ear or nose.

Human Papillomaviruses (HPV) are viruses that infect the skin and mucous membranes of the human body. Over a hundred different types of HPV have been identified. Some HPV species are transmitted by sexual activity and are pathogenic. HPV is considered to be the most common sexually transmitted infection in the united states. Hundreds of millions of women worldwide have infected once with HPV throughout their lifetime (about 70%), with the most prevalent among young women (20-30%). These viruses can cause infections of female external genitalia and lead to diseases of female external genitalia such as genital warts, dysplasias and cervical cancer.

Cervical cancer is a life-threatening disease and is currently the third most common cancer in women worldwide. Scientists believe that there is a strong link between cervical cancer and HPV development. Persistent HPV infection of the cervix can lead to cellular abnormalities including cervical epithelial neoplasia (CIN), precancerous lesions, and ultimately cervical cancer.

Fortunately, the slight cellular abnormalities that include CIN1 have a high degree of natural regression (> 60%), a condition that is usually tracked only by colposcopy. Moderate to severe CIN (CIN2 and CIN3) has a lower degree of natural regression and a higher risk of progression. Thus, patients with CIN2 and CIN3 are typically resected by surgical methods including diathermy, laser resection, and hysterectomy. About 90% efficacy, but with side effects interfering, leading to increased risk of bleeding, infection, stenosis, sterility and premature birth.

If left untreated, precancerous cells will develop into more severe forms such as malignant tumors and neuroendocrine malignancies. Like most other forms of cancer, the mode of treatment for cervical cancer depends on the stage of progression of the disease. Treatment of early stage cervical cancer is usually a variety of forms of surgery, while advanced cervical cancer is treated by surgery in combination with radiotherapy and chemotherapy. The most common chemotherapy for cervical cancer involves the use of cisplatin. It is estimated that about 11,000 women are diagnosed with cervical cancer each year, of which about 4,000 will die from the disease. Survival (greater than 5 years) depends on the stage of the disease and averages over 50%.

Photodynamic therapy (PDT) is a form of treatment using a combination of light and a photosensitizer. When irradiated at the appropriate wavelength, photosensitizers or "PDT drugs" react with oxygen in the tissue to form oxygen radicals that interact with organelles including mitochondria and cell membranes. These interactions cause cell necrosis or apoptosis (programmed cell death). PDT is currently used clinically to treat serious diseases including various skin diseases and the like.

A conventional product used in skin PDT is Metvix(Galderma, Switzerland) and Levulan(DusaPharmaceuticalsInc，Wilmington，USA)。

The range of photosensitizers is known from the scientific literature. One class of such compounds is toxic to the target cell or substance itself, or has luminescent properties when exposed to light. Such compounds have relatively high molecular weights and are typically ligand molecules such as phthalocyanines, chlorines, porphyrins, and psoralens. Another class of compounds more commonly used in the clinic are photosensitizer precursors, which do not themselves have phototoxicity or luminescence, but form photoactive compounds in vivo, such as endogenous porphyrins. Such compounds are typically 5-aminolevulinic acid (5-ALA) and derivatives of 5-ALA, such as 5-ALA esters, and are referred to hereinafter as "precursors"

There is no PDT or diagnostic product on the market today for cervical diseases, disorders or conditions. However, there are some scientific reports on clinical studies involving cervical PDT including PDT infected with human papilloma virus.

In a recently published study (P.Soergelletal, LasersinSurgeryandmedicine 40: 611-615(2008)), twenty-four patients with CIN2 or CIN3 or chronic CIN1 received topical treatment with a thermal gel formulation of 5-ALA hexyl ester. Then, the mixture is used at a temperature of 100J/cm²The patients are recommended to remain supine for 3 to 5 hours before the high light dose laser irradiation of (2) is continued for 17 minutes. After 2 to 3 months, clinical efficacy was evaluated and a second PDT treatment was provided to individuals who did not respond fully to the first PDT. All patients scored at 6 months after the first treatment and found a complete response rate of 63%.

From the above, it is known that this is time consuming for both the patient and the gynecologist. The patient will have to visit the gynecologist for medication, after which they have to lie supine for 3 to 5 hours, after which they visit the gynecologist again for irradiation. In addition, many patients who do not respond to the first treatment need to go through the process again.

The collective conclusion of these studies is that there is room for improvement in the clinical efficacy of PDT for the treatment of HPV and cervical cell abnormalities. Moreover, this process is time consuming for both the patient as well as the hospital staff. Similarly, there is room for improvement in the treatment of other conditions affecting the female reproductive tract and in the treatment of conditions affecting other orifices.

There are several patent documents describing various devices for vaginal, cervical drug delivery or optical type diagnosis or treatment.

US2008/0065003 discloses a LED-like cervical PDT device comprising an irradiation probe inserted into the cervical region. The LED array is arranged either within the illumination probe or in a handpiece (handleview) connected to the probe via a light guide. The device is connected to an external power source and light from the LED enters the cervix through a spherical reflector in the illumination probe.

GB2370992 discloses a LEDPDT device for cervical treatment. The device consists of a probe portion comprising an array of LEDs, shaped for insertion through the vagina to fit closely over the cervical os. The probe section is connected to the handpiece via a hollow shaft through which external air and power supply provide air and power to the LED array. The device is clamped in position for continued treatment.

It will be appreciated that these devices all require operation by a professional physician and are therefore commonly used in medical institutions such as hospitals or GP clinics. The patient must remain motionless during irradiation, which is inconvenient and limits the practical length of time during each treatment.

In addition, the photosensitizer must be applied to the cervical region before the device is used. With current methods, the patient typically waits several hours between application of the photosensitizer/precursor and irradiation.

Currently, PDT is a clinically insignificant method for the treatment of CIN and other diseases/conditions of the cervix. As described in the above reports, this is due to ineffective treatment results. Accordingly, there is a need for improved methods of treating cervical organ systems.

Disclosure of Invention

Surprisingly, the present inventors have found that the use of specific devices in combination with photosensitizers or precursors can improve the treatment of cervical cancer as well as other diseases, disorders and conditions, particularly those caused by HPV infection. Similar improvements can be made in the photodynamic treatment of other conditions affecting the female reproductive tract, such as vulvar epithelial neoplasia (VIN) or vulvar malignancy. Furthermore, PDT of cancerous or precancerous conditions or lesions of any other aperture of the human or animal body may be similarly improved.

According to one aspect, the present invention provides a radiation device for insertion into a body orifice to provide photodynamic therapy or diagnosis, the device comprising: a housing adapted to be fully inserted and secured within the aperture, the housing enclosing an LED lamp system and a power supply to power the LED lamp system, wherein the device operates independently when positioned within the aperture.

Unlike prior art devices, the device of the present invention does not require the patient to remain at the medical facility during treatment. Instead, use of the device will typically mean only one visit to the medical facility, followed by free exit of the patient. Ongoing treatment may be performed while the patient continues his or her daily activities.

This is because the device is adapted to be fully inserted and secured in the hole and does not need to be connected to an external power source or light source during operation. By "independently functioning" it is meant that the device can provide PDT illumination without the need for simultaneous connection to any external device. The device is thus completely self-contained and forms an enclosing unit comprising the light source and the power supply required for the photodynamic process.

Another advantage of the present invention is that irradiation is preferably performed at a very low fluence rate (fluencerate) and increases patient complianceComfort and minimize patient harm. Fluence rate F is the radiant power incident per unit area and is given in units of W/cm²And (6) measuring. At low fluence-rate (e.g., 10W/cm)²) Irradiation requires irradiation for a relatively long period of time, such as several hours, to achieve the light dose required to achieve a therapeutic effect, and therefore, such irradiation is not possible in clinical (hospital) facilities. However, it is known that the use of irradiation at low fluence rates significantly reduces patient discomfort (distress) during irradiation, and may also improve the impact of PDT by allowing a continuous accumulation of endogenous porphyrins (from precursors) and prevent oxygen consumption during irradiation (s.jacquetotal., "pdtwithhala/ppi xisenhancedyprodinglongingmittchoice", spiieproceedingmovingmotif ", spel.2972," optical methods for vascular treatment and detection ", ed.t.dougherty, SanJose, February1997, and m.sesharedientl., clinencerel 14(9), 2796-5 (2008)).

Thus, the device is not only more "patient friendly", but may also increase the efficacy of the treatment.

The shape of the housing may vary, but is typically designed so that it fits comfortably within the aperture and remains in place independent of the physical activity of the patient. When the target aperture is the female reproductive tract, a suitable shape for the exterior of the housing may be, for example, a shape similar to some contraceptive devices used for contraception, such as a FemCapAnd other similar devices intended to prevent the entry of semen into the uterus. For other apertures, other suitable shapes and configurations may be used, based on the shape as known for use as a suppository and/or medicinal pessary.

Although the present invention is directed to the treatment of human patients, it may also be used with devices used in the treatment of other animals. Thus, the shape of the housing will depend on the aperture to be treated and the anatomy of the animal for which the device is intended.

The device may comprise a slim housing, the walls of the aperture will wrap around the housing and secure it in place. The housing may be similar in size and shape to, for example, a tampon when the device is used in vaginal applications. The outer surface of the housing may be textured to improve the slip resistance of the device. The textured surface also facilitates providing a surface for delivering drugs to a body region in need of treatment.

To ensure comfortable and effective treatment for each patient, devices of different sizes and/or shapes may be manufactured. For example, in the case of cervical treatment, three sizes of devices may be provided for the following patients: (i) a patient who is not pregnant, (ii) a patient who is pregnant but not full term, and (iii) a patient who has born a child.

For some holes, such as the rectum, a simple "torpedo" shape will ensure that the device is inserted and secured. However, for other applications, other features may be present to ensure that the device is securely retained within the aperture during use. Thus, for vaginal applications, the housing preferably includes a flexible exterior that can adjust its shape to form a secure fit with the vaginal wall and allow the device to be used in vaginas of many different shapes and sizes. The flexible exterior also helps to reduce the risk of the device sliding or shifting over the extended treatment period of physical activity of the patient. Similar exteriors may be used for devices intended to be inserted into other apertures, if desired.

For insertion into the ear or nose, the device may be shaped based on known designs of ear or nose plugs.

The flexible outer portion may be formed of any material that is capable of adjusting its shape. For example, the flexible portion may be formed of an expandable, compressible, or deformable material. The housing, which is at least partially constructed of a deformable material, can adjust its shape during insertion to accommodate the diameter of the hole. Alternatively, an intumescent material may be used so that the exterior of the housing expands after insertion to firmly grip the wall of the (grip) hole. The expansion may be initiated by body heat, contact with a fluid, removal from the delivery device/tool, and the like.

Preferably, however, the flexible outer portion is formed of an elastomeric material. This allows the shape of the flexible portion to be changed while also providing an outward biasing force to hold the device in place. To achieve this effect, the outer diameter of the external device must be reduced in size to insert the device into the hole. The outer portion will then provide an outward force on the bore wall.

The elastomeric material may be any elastomeric material commonly used in medical devices, such as rubber, latex, silicone, or other natural, semi-synthetic, or synthetic polymers or copolymers.

The flexible exterior may be any shape that can form a secure fit with the walls of the hole. For example, the flexible outer portion may be provided in the form of a number of discrete legs, ridges or other protrusions spaced radially and/or longitudinally and extending outwardly from the housing. In other embodiments, the flexible exterior may form a continuous exterior surface of the housing. This surface may form all or part of the exterior of the housing. For example, the outer portion may be a disk or cup-shaped section at the front or rear of the device, or a cover that extends along the entire length of the housing.

In a preferred embodiment, the flexible outer portion forms a continuous surface tapering towards the rear end of the device, i.e. the end of the device closest to the entrance of the bore in use. For example, the outer portion may be generally frustoconical in shape.

While it is only necessary that the exterior of the housing be flexible, in certain preferred embodiments, the entire housing is flexible. Manufacturing a device with a flexible outer shell increases the comfort of the device and simplifies construction, as only a single material is required.

Preferably, the housing comprises a treatment surface from which the LED system is configured to emit radiation. The device may be configured to provide radiation to the bore wall, in which case the treatment surface may be the outer peripheral surface of the housing. The treatment surface preferably has a size and/or shape selected for complementary mating with the treatment area, and is preferably sized to face the entire area requiring PDT. The LED lamp system and treatment surface are preferably configured so that radiation is emitted toward the treatment surface with sufficient proximity and intensity to achieve the desired therapeutic effect.

The device may be configured to provide radiation to a specific region inside the bore. Thus, when the device is in use, the device may comprise a treatment surface configured to direct and/or focus radiation onto a specific area inside the aperture. In a preferred embodiment, the device is adapted for use in PDT of the cervix. Thus, preferably, the treatment surface is shaped to cover the cervical opening in use. Thus, when the device is properly inserted into the vagina, the treatment surface will cover the opening of the cervix, thereby allowing the emitted light energy to irradiate the cervical region.

The size of the treatment surface should be such that it matches the entire cervix, e.g., 20-50mm in diameter, more preferably 20-35mm in diameter, and most preferably 22-30mm in diameter.

Preferably, the treatment surface is at least partially transparent to allow light from the LED to pass through the treatment surface to provide the desired PDT treatment or diagnosis. In some embodiments, the treatment surface may be completely transparent to light having a wavelength required for PDT treatment and emitted by the at least one LED. Preferably, however, the material of the treatment surface and/or other materials between the treatment surface and the light emitting part of the LED lamp system are configured to diffuse the light to evenly distribute the light from many LEDs. In one embodiment, a transparent material is used to form the housing and treatment surface around the LED lamp system, thereby functioning as a housing for the lamp system and a diffuser for the light. In an alternative embodiment, the treatment surface is formed using a transparent material, while the housing is formed using a non-transparent material. This will ensure that only the area needed for treatment will be irradiated, while other areas in contact with the device will not be irradiated. Preferably, transparent silicone is used as the material of the treatment surface that acts as a diffuser for the emitted light.

In some preferred embodiments, at least one LED may be disposed on or extend from the treatment surface. In such embodiments, light is not required to pass through the treatment surface and thus its opacity is not constrained.

In a preferred embodiment, the treatment surface is concave. This may help direct the emitted light to a treatment surface such as the cervix.

In embodiments designed to provide radiation to the cervix, the apparatus includes a protrusion extending from the treatment surface. Preferably, this protrusion forms a cylindrical tube. This can be used to assist in the correct positioning of the device within the vagina and to direct light towards the cervical canal. In the latter case, the tube functions as a light pipe.

Preferably, the flexible exterior is located posterior to the treatment surface. This prevents any interference with the radiation therapy. In preferred embodiments where the outer portion is a continuous surface, the outer portion may extend from the treatment surface to the rear of the device, tapering outwardly such that the widest cross-section of the outer portion is located behind the treatment surface.

The device includes an LED lamp system that is capable of operating independently when the device is positioned within the aperture.

The lamp system may comprise one LED or preferably an array of LEDs. A particularly preferred LED array for cervical PCT comprises 3 to 15 LEDs. The term "LED" is intended to cover any form of light emitting diode, such as an OLED (organic light emitting diode).

The energy consumption of the LED lamp system per unit time should be such that the tissue is heated without causing undue discomfort or injury to the patient. The radiation will typically be at a rate of 10 to 200J/cm²E.g. 50J/cm²The dosage level of (a). Accordingly, the LED lamp system is preferably configured to provide 0.5 to 100mW/cm in operation²In the range, most preferably from 1 to 10mW/cm²Fluence rate over a range. This low fluence rate results in a total dose being applied over a relatively long period of time, such as several hours. As noted above, this is beneficial in reducing patient discomfort and improving treatment efficacy.

The wavelengths of light used for radiation can be selected to achieve an effective photodynamic effect, and thus the LEDs are selected for their ability to emit wavelengths of light suitable for this effect. In a preferred embodiment, at least one of the LEDs emits, in use, light having a wavelength in the range of 300-800nm, as has been found to be particularly effective in the range of 500-700 nm. Of particular importance are wavelengths comprising 630 and 690 nm. Thus, preferably, at least one of the LEDs emits, in use, light having a wavelength in the range of 630-690 nm. In the most preferred embodiment, especially if the device is used with a mixture comprising a photosensitizer precursor selected from 5-aminolevulinic acid or a derivative thereof, such as an ester, red light (600-670nm) is used, since light at this wavelength is known to penetrate tissue well. In some embodiments, the LED lamp system includes a filter to ensure that only light within a particular wavelength range, such as those described above, is emitted from the device. The treatment surface can be designed to transmit only light having these preferred wavelengths.

The power source preferably comprises one or more batteries. The battery should preferably operate by using an electrochemical reaction with chemicals that are not highly toxic to the patient if the device is broken or leaked in the human body. Suitable batteries include lithium batteries or equivalents with sufficient capacity to store up to ten years. For example, a LiMnO of 1/2AA size may be used₂A battery. The slow loss of charge and the small volume of lithium ion batteries make them particularly suitable for use as power sources for devices. To increase the safety of the device, it is preferred that the power supply is sealed within the housing. By sealed is meant that the housing is liquid tight in use to prevent liquid from leaking into or out of the device.

At its most basic, the lamp system may simply include electrical connections for the power supply to the one or more LEDs. With this arrangement, the headlamp system will be activated immediately at the insertion device to turn on one or more LEDs. The device will then be inserted into the hole where the LED will illuminate the treatment area until the device is removed or the power source is exhausted.

The lamp system may be activated by a switch. In order to keep the device sterile and to keep the power supply and other elements of the device enclosed, the switch is preferably enclosed within a housing and configured to be operated while sealed within the housing. The switch may be a mechanical switch located under a flexible portion of the housing, the elasticity of the flexible portion allowing operation of the switch. Alternatively, the switch may be operated by an electric or magnetic field transmitted through the housing. A magnetically operated switch may be made by using a magnet on the outside of the housing to keep a "normally closed" reed switch open. When the magnet is removed, the reed switch will close and this can be used to activate the device.

In simple systems using only a power supply and LEDs, it is difficult to control the dose level, as the exact lifetime and power output of the power supply will vary. Furthermore, the illumination provided by the LED array will be constant. To avoid unacceptable heating of the tissue, it may also be advantageous to use low intensity light, and the device is capable of providing pulsed light.

Therefore, preferably, the lamp system further comprises a control circuit, such as a microcontroller or microprocessor, for regulating the radiation provided by the at least one LED. The control circuit of the lamp system may be activated by a switch as described above. In a preferred embodiment, the control circuit comprises a timer. The lamp system may then be programmed to begin shining at a predetermined time interval after startup. This ensures that a sufficient time elapses from the start-up to the start of irradiation. For example, to ensure uptake or accumulation of the porphyrin, a period of time is required after application of the photosensitizer or prodrug. The duration of the irradiation may also be tightly controlled, as the control circuitry may be configured to turn off the irradiation after a predetermined dosing time has elapsed. The device may be repeatedly irradiated (PDT again) after a period of time, e.g. three hours, for further accumulation of endogenous photosensitizer (from the precursor) after the first irradiation.

Further, the control circuit may be configured to provide pulsed illumination. This may be achieved by providing a function generator within the microprocessor. As mentioned above, pulsed light is advantageous to ensure that unacceptable heating of the tissue does not occur. Furthermore, providing an irradiation interval enhances tissue oxygenation and PDT effects. Furthermore, this allows for the re-accumulation of endogenous porphyrins in surviving cells treated with repeated irradiation. The frequency and length of the pulses can be selected and set within the control circuit as required by the treatment regime.

In one embodiment, the control circuit is programmable by a user. This enables adjustment of length, intensity and irradiation pattern to suit individual treatment. Suitable forms of readable and writable memory include EPROM, EEPROM, flash memory and the like. However, the control circuit memory is preferably read-only (ROM) and programmed at the time of manufacture.

Access to the control circuitry may be achieved through a user interface on the device. By answering a series of questions, the user can set an initial delay period, a dosing cycle, the number and length of light pulses, etc. The interface may be integrated with the device. Thus, it may comprise a small button that can be pressed by a suitable tool or reed switch. Each button or switch may initiate a given preset condition such as light dose, intensity, pulsed/steady light, etc.

It is important that all electrical components of the lamp system and the power supply are sealed within or to the housing when in use. Therefore, the control circuit should preferably be sealed within the housing. As described above, the LEDs may be arranged such that they protrude from the housing. However, it is preferred that the LED lamp system is entirely sealed within the housing in use.

In some embodiments, the user interface is accessible through a flexible region of the housing. Alternatively, the housing may include a sealable opening that provides access to the interface.

However, providing a user interface increases the size of the lamp system, which may be undesirable in certain applications. Thus, alternatively, the control circuit may comprise a receiver for connecting a remote terminal. At this time, the specific program command may be communicated from a remote terminal such as a computer to the control circuit.

In some embodiments, the receiver includes an input port adapted for connection to a cable. In these embodiments, the input port is shaped to receive, for example, a USB or other male connector.

The inlet port must be sealed in use. Thus, the housing may comprise a plug for insertion into the port. Alternatively, the housing may be composed of two parts which may be connected by a screw thread, a push-fit connection or a bayonet fitting. This connection includes a seal to ensure that, in use, the control circuitry is sealed within the housing.

Alternatively, the program commands may be transmitted to the device over a wireless connection. For example, the receiver may be an infrared or radio wave receiver. This has the following advantages: physical input ports are not required and the control circuitry may instead be permanently sealed within the housing.

Preferably, the control circuit further comprises a feedback system. This enables the control circuit to adjust during the treatment program to account for deviations in the expected LED performance.

For example, the feedback system may include a light monitor or other direct or indirect monitor to determine the light dose that has been administered to the patient. In such systems, the control circuit may be programmed to turn off the LEDs after a predetermined dose is reached, rather than a predetermined time.

Alternatively, the dosimeter may replace the timer when the LED is not operating as intended. For example, if the power supply fails, the output of the LED may be reduced. Therefore, continuous irradiation over a predetermined time is required to obtain a full dose. Conversely, if the power output of the LED is stronger than expected, the illumination may be terminated before a predetermined time interval, or the duration of each pulse may be shortened to prevent overheating of the tissue.

Another optional feature of the control circuit is one or more performance indicator lights for informing the user whether the device has operated properly or whether an error has occurred. The control circuitry may be configured to provide a signal to the user when the treatment is complete indicating that the device is removable. For example, an audible and/or visual signal, such as an alarm tone and/or a light signal, may be provided. Alternatively or additionally, vibration may be used as a signal to indicate termination of treatment. Typically, the patient should be informed of the length of treatment so that the signal can be used to confirm the intended termination of treatment and thus without undue disturbance.

Advantageously, because the control circuit can be used to turn off the LED at the end of a treatment cycle, there is no significant detrimental effect on the patient if the device is held for an insertion time longer than the treatment time. However, it is anticipated that the patient will want to know when the treatment has ended and the device can be removed.

Preferably, the microprocessor contains some or all of the features described above for the control circuit.

Preferably, the apparatus further comprises a lens system configured to provide uniform irradiation at the treatment area. The treatment surface may function as a lens system. For example, this surface may be formed of silicone or another material, including surface elements for diffusing light emitted by the LED.

In use, the device is preferably placed in the hole by a physician, nurse or other person with experience or knowledge in the relevant field. However, in some cases the patient may choose to insert the device himself.

In a preferred embodiment, the device includes a handle at its rear end. The patient or medical operator may use this handle to firmly grip the device during insertion and removal.

The handle may be an elongated arm extending from the device housing. However, in a preferred embodiment, the handle is arcuate in shape, as a smooth edge will prevent the possibility of discomfort or injury to the patient. In some preferred embodiments, the arcuate handle is attached to the device at two or more points on the flexible exterior. It is advantageous that the flexible portion will be pulled inwardly when the handle is grasped and pulled, thereby facilitating removal of the device. A similar effect can be achieved by connecting a wire or cable to at least two locations on the exterior, although the latter embodiment does not aid in insertion.

Thus, preferably, the device comprises a removal mechanism attached to two or more locations of the flexible exterior and comprising a central grip.

Another option is to use a special instrument, such as a pair of forceps, to place (and remove) the device.

Advantageously, the device is designed for a single use and is disposed of after the single use. Preferably, the device includes one or more features that facilitate single use and/or prevent reuse. For example, the power source may be configured to provide power sufficient for only a single use, i.e., the power source is exhausted after the desired treatment is completed. The power source may be configured not to be charged and/or the control circuit may not be able to charge the power source. The control circuit may be configured to prevent reuse by its programmed features, and/or it may include a disabling mechanism that destroys the circuit or software upon triggering. In use, to prevent interference by the patient, the control circuit may also be configured to selectively disable if interference is detected. By forcing a single use, patient safety is improved and sterility of the device is ensured strictly.

The device of the present invention may be used to provide PDT according to the following method. First, a mixture comprising a photosensitizer or a precursor thereof is applied to the area to be treated by a physician, can be applied using a specialized applicator, or the targeted area is treated by a systemic acting drug. The systemically acting drug may be administered, for example, intravenously or orally. The programmed device is then turned on and inserted. The patient may then immediately leave the medical facility and continue their daily routine while the treatment area receives radiation from the device. Thus, treatment can occur over an extended period of time without inconvenience to the patient. This allows the use of low fluence rates, increasing the efficacy of the treatment. After treatment is complete, the patient may return to the medical facility to remove the device, or remove the device on their own. The device may be discarded or returned to the medical facility for disposal.

In a preferred embodiment, the device of the present invention further comprises a drug delivery system. The drug delivery system may include a drug carrying area on the housing, such as a drug carrying area on the treatment surface. The textured surface may be used to carry a mixture of photosensitizers or precursors, or the treatment surface itself may function as a drug delivery system without any further modification. Alternatively, the drug delivery system may comprise a reservoir for containing a mixture comprising the photosensitizer or a precursor thereof (hereinafter "mixture").

An advantage of this embodiment of the invention is that the patient does not need to wait several hours between application of the mixture and irradiation in the hospital, as is the case in existing PDT procedures. The device may be automatically illuminated immediately upon application, or preferably after a period of time. Furthermore, only one intrusive procedure (invasiveprocedure) is required.

Optionally, the drug delivery system further comprises a physical, mechanical or electrical system associated with the delivery. This optional system may include, for example, a filter, a membrane, one or more reservoirs configured to deliver a photosensitizer or precursor based on a predetermined protocol for drug delivery or based on body conditions such as pH, osmotic pressure, temperature, pressure, water content of the surrounding environment. However, most simply and most commonly, the most preferred drug delivery system is only a single drug carrying area for containing the mixture, and in the most preferred embodiment, the drug delivery system is the treatment surface itself.

In this preferred embodiment, the method of use is similar to that described above, except that the mixture is not applied to the treatment area in a separate step. Instead, the mixture is applied to a drug-carrying area, such as a treatment surface, and thus to the body when the device is inserted into the hole. The above irradiation is subsequently performed.

The mixture may be supplied with the apparatus. For example, the drug delivery system, i.e. the drug carrying area or reservoir, preferably the treatment surface, may be provided with a cover, such as a foil or cap, to seal the mixture within the device until use. Prior to insertion, the cap is removed so that the mixture can be released. Alternatively, the device may be supplied separately from the mixture. This enables the physician to select the optimal mixture for a particular condition and add this mixture to the drug delivery system, i.e. the drug carrying area or reservoir, preferably the treatment surface, prior to insertion.

The mixture to be used by the device, whether pre-filled or applied to the device prior to use or applied separately to the treatment surface, may comprise any suitable photosensitizer or photosensitizer precursor.

The range of photosensitizers is known from the scientific literature. As noted above, one class of such compounds is inherently toxic to the target cell or substance, or possesses luminescent properties upon exposure to light. Such compounds have a relatively high molecular weight and are usually ligands such as phthalocyanines, chlorines, porphyrins or psoralens. Another class of photosensitizers are compounds which are not themselves toxic or luminescent, but which form such active compounds in vivo. Such compounds, referred to herein as precursors, are typically 5-aminolevulinic acid (5-ALA) and derivatives of 5-ALA, such as 5-ALA esters. Such compounds may be used or provided by the device of the present invention.

5-Aminolevulinic acid (5-ALA) and its derivatives are the most clinically useful precursors known in the art. These compounds are converted in vivo to protoporphyrin ix (ppix), which is a photosensitizer capable of absorbing light and producing singlet oxygen upon contact with oxygen. Singlet oxygen is very reactive and reacts rapidly with various cellular biomolecules leading to cell death.

5-ALA and its derivatives are well known and used in methods of photodynamic therapy (PDT) for the treatment of various abnormalities or disorders of the skin or other epithelial organs or mucosa, in particular cancer or pre-cancerous lesions, as well as certain non-malignant lesions, such as skin diseases, e.g. psoriasis, Actinic Keratosis (AK) and acne. 5-ALA (Levulan)Dusa) and 5-ALA methyl ester (Metvix)Galderma, Switzerland) is a commercially available therapeutic product for PDT treatment of actinic keratosis and basal cell carcinoma.

The use of 5-ALA and its derivatives, such as 5-ALA esters in PDT, is well known in the scientific and patent literature (see, e.g., WO2006/051269, WO2005/092838, WO03/011265, WO02/09690, WO02/10120 and US 6034267). All such 5-ALA derivatives and pharmaceutically acceptable salts thereof are suitable for use in the devices described herein.

Esters of 5-aminolevulinic acid and its N-substituted derivatives are preferred precursors in the mixtures used according to the invention. Those compounds in which the 5-amino group is unsubstituted, i.e. ALA esters, are particularly preferred. Such compounds are well known and described in the literature (see, e.g., WO96/28412 and WO02/10120 to PhotocureASA).

Esters, i.e. alkyl esters, or more preferably substituted alkyl esters, of 5-aminolevulinic acid with substituted or unsubstituted, preferably substituted, alkanols are particularly preferred photosensitizers for use in the present invention.

Examples of such precursors include those of the general formula (I):

R² ₂N-CH₂COCH₂-CH₂CO-OR¹(I)

wherein the content of the first and second substances,

R¹represents a substituted or unsubstituted alkyl group; and is

Each R is²Independently represent a hydrogen atom or R¹And (4) a base.

As used herein, unless otherwise specified, the term "alkyl" includes any long or short chain, cyclic, straight or branched chain, or saturated or unsaturated aliphatic hydrocarbon group. Unsaturated alkyl groups can be mono-or polyunsaturated and include alkenyl and alkynyl groups. Unless otherwise specified, these groups may contain up to 40 carbon atoms. However, preference is given to alkyl groups comprising up to 30, preferably up to 10, more preferably up to 8, particularly preferably up to 6, for example up to 4, carbon atoms.

In the compounds of formula I, R¹The radical is a substituted or unsubstituted alkyl radical. If R is¹Is a substituted alkyl group, one or more substituents or a linking alkyl group and/or a interrupting alkyl group. Suitable substituents attached to alkyl groups may be selected from: hydroxy, alkoxy, acyloxy, alkoxycarbonyloxy, amino, aryl, nitro, oxo, fluoro, -SR₃、-NR³ ₂and-PR³ ₂Wherein R is³Is a hydrogen atom or C_1-6Alkyl group of (1). Suitable substituents for interrupting the alkyl radical areFrom: -O-, -NR₃-, -S-or-PR₃。

If R is¹Is a substituted alkyl group, preferably one or more aryl substituents, i.e. an aryl group, preferably one aryl group.

As used herein, the term "aryl" refers to an aromatic group, which may or may not contain heteroatoms such as nitrogen, oxygen, or sulfur. Aryl groups containing no heteroatoms are preferred. Preferred aryl groups include up to 20 carbon atoms, more preferably up to 12 carbon atoms, such as 10 or 6 carbon atoms. Preferred embodiments of aryl are phenyl and naphthyl, especially phenyl. Furthermore, the aryl group is optionally substituted with one or more, more preferably one or two substituents. Preferably, the aryl group is substituted in the meta or para position, most preferably in the para position. Suitable substituents include halogenated hydrocarbon groups (e.g., trifluoromethyl), alkoxy groups (preferably alkoxy groups having 1 to 6 carbon atoms), halo groups (e.g., iodo, bromo, preferably chloro and fluoro), nitro and C_1-6Alkyl (preferably C)_1-4Alkyl groups). Preferred is C_1-6The alkyl group of (b) includes methyl, isopropyl and tert-butyl, especially methyl. Particularly preferred aryl substituents are chloro and nitro. However, it is even more preferred that the aryl group is unsubstituted.

Preferred such R¹The radicals are benzyl, 4-isopropylbenzyl, 4-methylbenzyl, 2-methylbenzyl, 3-methylbenzyl, 4- [ tert-butyl ] benzyl]Benzyl, 4- [ trifluoromethyl ]]Benzyl, 4-methoxybenzyl, 3, 4- [ dichloro ] benzene]Benzyl, 4-chlorobenzyl, 4-fluorobenzyl, 2-fluorobenzyl, 3-fluorobenzyl, 2, 3, 4, 5, 6-pentafluorobenzyl, 3-nitrobenzyl, 4-nitrobenzyl, 2-phenylethyl, 4-phenylbutyl, 3-pyridyl-methyl, 4-biphenyl-methyl and benzyl-5- [ (1-acetoxyethoxy) -carbonyl]. More preferred R¹The radicals are benzyl, 4-isopropylbenzyl, 4-methylbenzyl, 4-nitrobenzyl and 4-chlorobenzyl. Most preferred is benzyl.

If R is¹For substituted alkyl, one or more oxygen-containing substituents are preferred. Preferably, such groups are straight-chain C substituted by one, two or three oxygen-containing groups_4-12An alkyl group.Examples of such groups include 3, 6-dioxa-1-octyl and 3, 6, 9-trioxa-1-decyl.

If R is¹Is unsubstituted alkyl, preferably R¹The radical is a saturated straight-chain or branched alkyl radical. If R is¹Is a saturated straight-chain alkyl radical, preferably C_1-10A linear alkyl group. Representative examples of suitable straight chain alkyl groups include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, and n-octyl. Particularly preferred is C_1-6Straight chain alkyl groups, most preferably methyl and n-hexyl. If R is¹In the case of saturated branched alkyl groups, such branched alkyl groups preferably consist of 4 to 8, preferably 5 to 8, linear carbon atoms in the main chain, the branch being one or more C_1-6Alkyl, preferably C_1-2Alkyl group. Examples of such saturated branched alkyl groups include 2-methylphenyl, 4-methylphenyl, 1-ethylbutyl and 3, 3-dimethyl-1-butyl.

In the compounds of formula I, each R²Independently represent a hydrogen atom or R¹And (4) a base. Particular preference is given according to the invention to those compounds of the formula I in which at least one R is²Represents a hydrogen atom. In particularly preferred compounds, each R is²Represents a hydrogen atom.

The most preferred precursors for use in the mixture together with the device according to the invention are compounds of formula I and pharmaceutically acceptable salts thereof, wherein R is¹Is C₁-C₆Alkyl radicals, e.g. hexyl, more preferably straight-chain C₁-C₆Alkyl, e.g. n-hexyl, and two R²Represents hydrogen, i.e. 5-ALA hexyl ester and pharmaceutically acceptable salts thereof, preferably the HCl salt. The most preferred precursor is 5-ALA hexyl ester and the most preferred pharmaceutically acceptable salt of 5-ALA hexyl ester is the HCl salt.

The mixture comprising the photosensitizer or precursor to be used with the device of the invention may be any type of pharmaceutical formulation and may be prepared by any conventional method in the art (see e.g. WO02/10120, photoceuasa). For example, esters of 5-ALA may be prepared by reacting 5-ALA with a suitable alcohol in the presence of a base. Alternatively, the compounds used in the present invention are commercially available (e.g. from PhotocureASA, Norway).

Preferred formulations are non-liquid (aqueous and non-aqueous), solid such as dusting powders (dusting powders), tablets or suppositories, semi-solid such as creams, ointments, gels or pastes, foam formulations or other expandable formulations (e.g. based on heating to body temperature) and patch-like formulations/systems. The components in the mixture are the same as in the pharmaceutical products on the market and a list of such components can be found in the reference book for pharmaceutical excipients.

Importantly, the formulation is such that the mixture is fully absorbed into the tissue to be treated and is transparent so as not to interfere with the irradiation. As noted above, systemically applied mixtures may also be utilized, such as drugs administered intravenously to a patient.

In another aspect, the invention provides a method of photodynamic therapy of a treatment area within a body orifice, the method comprising: a mixture containing a photosensitizer or precursor is applied to the treatment area and a radiation device according to the invention is inserted into the aperture such that the LED lamp system of the radiation device operates to provide irradiation to the treatment area.

The method may comprise the step of selecting a device of suitable size and/or shape. First a device is selected that can be adapted to the target hole and secondly a device is selected that is adapted to different patient conditions. For example, the device for cervical treatment will preferably be selected from a range of sizes depending on the pregnancy history of the patient.

The mixture may be applied to the treatment area prior to insertion of the device, and this may be accomplished by direct application of the mixture using a suitable applicator, or by a systemically applied drug, such as a drug administered intravenously to the patient. In an alternative preferred embodiment, the mixture is applied via the drug delivery system of the device such that the application step of the mixture and the insertion of the device occur simultaneously. The drug delivery system may comprise a drug carrying area or reservoir, or may simply be the treatment surface of the device described above.

Preferably, the lamp system provides 10 to 200J/cm²E.g. 50J/cm²The dosage level of (a). The lamp system may have the features described above.

The device may be provided separately from the mixture or from the mixture already contained within the drug delivery system. Alternatively, the device may be provided in the form of a kit comprising the device and at least one compound for use with such device.

The devices and methods of the present invention for photodynamic therapy may be combined with other therapeutic procedures, such as administration of other therapeutic agents. These therapeutic agents may be administered into the body prior to or simultaneously with placement of the device in the hole, or may be administered by other routes of administration (e.g., oral, intramuscular, or transdermal). Typically, such drugs include hormones, antibacterial agents, antifungal agents, antiviral agents, anticancer agents, or combinations of these drugs.

As mentioned above, while some of the preferred features of the present invention have been described in relation to providing PDT for the vagina and cervix, it will be appreciated that these feature devices may be advantageously included in devices for other body orifices, such as the devices for the rectum, ear or nose described above. The present invention is not limited to the particular well in which it is used, and provides devices and methods that may be advantageously used to treat a variety of conditions in different wells.

Drawings

Some preferred embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

FIGS. 1A and 1B show perspective and cross-sectional views, respectively, of a first preferred embodiment of a radiation device;

FIGS. 2A and 2B show a perspective view and a cross-sectional view, respectively, of a second preferred embodiment of a radiation device;

FIGS. 3A and 3B show perspective and cross-sectional views, respectively, of a third preferred embodiment;

FIG. 4 shows a schematic diagram of a control circuit used in the radiation device of the preferred embodiment;

figures 5A and 5B show an isometric perspective view and a cross-sectional view, respectively, of a fourth preferred embodiment of a radiation device;

6A, 6B, 6C and 6D show perspective, side, end and cross-sectional views of a fifth preferred embodiment of a radiation device; and is

Fig. 7A, 7B, 7C and 7D show perspective, side, end and cross-sectional views of a fifth preferred embodiment of the radiation device.

Detailed Description

Fig. 1A and B show a first embodiment of a radiation device 10 for photodynamic therapy. The apparatus 10 of the first embodiment is configured for use in photodynamic therapy of the cervix. The device 10 comprises a flexible housing 1. The outer part 7 of the housing is generally frusto-conical in shape and tapers outwardly from the front to the rear of the device. The outer portion 7 is resilient such that in use the outer portion 7 presses against the vaginal wall to securely hold the device 10 in place.

A lamp system 12 is enclosed within the housing 1. The system 12 includes an array of LEDs 5 and a control circuit 6. This control circuit 6 will be discussed in detail below. It provides power to the LEDs 5 so that in use these LEDs 5 will illuminate the cervix.

The front end of the housing 1 forms a treatment surface 2. This treatment surface 2 is shaped to cover the cervical opening in use, thereby ensuring that radiation from the LED5 is directed to the treatment area. The treatment surface 2 comprises an annular contact surface 2a and a recess 2 b. Typically, the contact surface 2a has a diameter of 20 to 50 mm.

To assist in removing the device 10, the thread 4 is attached to the outer portion 7 in at least two locations. When the cord 4 is gripped and pulled, the outer portion 7 is pulled inwardly, thereby facilitating removal of the device 10.

Fig. 2A and 2B show an alternative embodiment of an apparatus 20 intended for cervical treatment. In this embodiment, the device 20 also includes a resilient outer portion 27 that is generally frustoconical in shape. Furthermore, the treatment surface 22 is also formed by an annular contact surface 22a and a recess 22 b. However, in this embodiment, only the control circuit 26 is sealed in the housing 21. The LED array 25 protrudes into the recess 22b of the contact surface 22.

In addition, the device 20 includes an arcuate handle 23 extending from the rear end of the housing 21. Unlike the wire used in the first embodiment, the handle 23 of the device 20 may be used to assist in insertion and removal of the device.

A third embodiment of the device 30 is shown in fig. 3A and 3B. Again, the main shape of the housing 31 and the outer part 37 remains unchanged.

Device 30 is similar in design to device 10. The LED array 35 and the control circuit 36 are both housed within the housing 31, and wires 34 are provided to assist in the removal of the device 30.

However, there are two important differences. First, the protrusion 38 extends from the treatment surface 32. This protrusion 38 forms a drug delivery system and a light pipe through which light from the LED35 is directed. This protrusion 38 is shaped to contact the cervical canal in use. This tube allows the photosensitizer or precursor and light from LED35 to be delivered to the cervical canal (endocervix), thus increasing the ability of device 30 to provide photodynamic therapy.

In addition, the recess 32b of the treatment surface functions as a reservoir within which the treatment mixture 39 may be contained. It can be seen that the recesses 2b, 22b of the previous embodiment are also suitable for containing this mixture 39. Thus, the device of the present invention also functions as a drug delivery device. Mixture 39 contains a photosensitizer or precursor suitable for use in photodynamic therapy or diagnosis. By placing this mixture 39 within the device 10, 20, 30, the mixture can be applied to the treatment area when the device is inserted. In addition, delivery of the mixture to the cervical canal can also be achieved by coating the mixture with the protrusions 38 prior to inserting the device into the patient. Thus, the patient need only undergo one invasive step before kinetic treatment or diagnosis can be performed.

Figure 4 shows a control circuit suitable for use in any of the preferred embodiments of the irradiation apparatus. This control circuit 40 derives power from a lithium battery 41 which is used to power an LED array 45. The control circuit 40 includes a microprocessor 42 that controls the operation of the LED array 41.

For example, the microprocessor 42 may include a timer and a memory in which the dosage regimen may be programmed. Thus, the LED array 45 may be operated to illuminate the treatment area for a predetermined length of time, and the LED array 45 may be configured to operate continuously or to provide pulsed illumination. Further, the control circuit 40 includes a light sensor 43. This forms a feedback circuit that enables the microprocessor 42 to adjust the operation of the LED45 to ensure that any abnormalities or malfunctions of the control circuit 40 do not affect the dose received by the patient.

Before inserting the device, switch 46 is closed to begin operation of control circuit 40. For example, this may initiate the timing of a "delay time" after which the microprocessor 42 will begin operation of the LED array 45 according to a programmed scheme. After a predetermined time, or upon completion of a certain light dose (as determined by light sensor 43), microprocessor 42 will turn off LED 45. The device can then be removed.

In a modified embodiment, the control circuit further comprises two running indicator lights (not shown). The two operational indicators may include two LEDs, one of which illuminates when the device is operating correctly and a second of which illuminates when any faults occur; the combination of lights indicates a particular fault. Alternatively, only a single running light may be provided which illuminates after the correct operation of the device is complete and remains off when any fault occurs. The control circuit may comprise an alarm device for providing an audible signal and/or a vibration device for providing a signal by vibration.

The system alerts the patient and the medical operator if any failure occurs that prevents the patient from receiving the correct dose. The signal from the control circuit may also indicate that the treatment has been successfully completed.

Fig. 5A and 5B show a fourth embodiment of the irradiation device, and in this embodiment the device is configured for treating a wall of a hole in a human or animal body. The aperture may be, for example, vaginal, rectal, ear or nasal. The particular size and shape of the device may vary depending on the size and shape of the aperture.

The device includes a housing 51 enclosing an array of LEDs 54 and a power and control circuit 55. The housing 51 of the illustrated embodiment is in the shape of an elongated cylinder having hemispherical ends 52. This shape is the preferred shape for insertion into the vagina and rectum, and for insertion into other holes, a conical end (not shown) may be used in place of the hemispherical end 52. Smaller devices may be used for insertion into the nose and this shape is typically adjusted to more closely approximate a cone. Smaller sizes and slimmer shapes can be used to insert into the ear. At the opposite end of the hemispherical end 52 (or alternatively the conical end), the device has a ring 53 to facilitate insertion and removal, and where necessary, attachment of wiring.

The elongated cylindrical portion of the housing 51 includes a treatment surface around its outer circumference. The treatment surface will contact the inner wall of the hole to provide radiation to the treatment area on the wall of the hole. To this end, the LED lamp system includes an array of LEDs 54 located below the treatment surface around the elongated cylindrical portion. The LED54 is configured to provide illumination through a cylindrical treatment surface. In modified embodiments, the LED may also be located below the treatment surface of the hemispherical or conical end of the device. The housing 51 is made of clear silicone and it also forms a treatment surface that can function as a drug delivery system. The transparent silicone also acts as a lens that diffuses the light emitted by the LED array and thereby acts to evenly distribute the emitted light.

Fig. 6A, 6B, 6C and 6D show a fifth embodiment of an irradiation device for photodynamic therapy. Fig. 6D is a cross-section taken along line a-a of fig. 6C. The device 60 of the fifth embodiment is configured for use in cervical photodynamic therapy and has a housing 61, the housing 61 comprising an upper housing part 61a having similar features to the first and second embodiments, and additionally having a lower cylindrical housing part 61b extending below the upper housing part. The upper housing portion 61a is flexible and includes an outer portion 67 that is generally frustoconical and tapers outwardly from the front end toward the rear portion of the device 60. The outer portion 67 is resilient such that in use the outer portion 67 presses against the vaginal wall to securely hold the device 60 in place. The shape of the upper housing portion 61a and its exterior 67 can be seen most clearly in fig. 6D.

The LED lamp system 61 is sealed in an upper housing 61a and has similar features to the above-described embodiment. The power supply for the lamp system is a battery 68 enclosed in a cylindrical housing part 61 b. The battery is an 1/2AA size battery with a cylindrical housing portion 61b formed relatively tightly around the battery. The control circuit 69 is also enclosed with the battery, advantageously in the form of a PCB having the same diameter as the battery diameter, for efficient use of space.

The front end of the upper housing 61a forms a treatment surface 63, which is a lens formed of a transparent material that covers the LEDs of the LED lamp system 62. As a fourth embodiment, this material may be a transparent silicone which also forms the remainder of the flexible housing of the device 60. The over-molding may be performed using opaque white silicone to cover the sides of the upper housing portion 61a, over-mold around both the outer portion 67 and the sides within the outer portion 67, and completely cover the cylindrical portion 61 b. The white overmold acts as a reflector for the lens for the treatment surface and hides the internal components in the cylindrical portion, which may include a battery 68 and control circuitry 69. In one embodiment, the underside surface of the housing portion 61a may be black to protect vaginal mucosa that is exposed to emitted light without treatment.

The treatment surface 63 is shaped to cover the cervical opening in use, thereby ensuring that radiation from the LED is directed to the treatment area. The treatment surface 63 comprises a contact surface 63a typically having a diameter of 22 to 30 mm. In a preferred embodiment, the contact surface 63a functions as a drug delivery system, i.e. a drug carrying area or reservoir, and carries a photosensitizer or precursor.

At the base of the cylindrical housing portion 61b, a ring 64 is provided to facilitate insertion and removal of the device. If desired, a wire may be attached to the loop 64. Alternatively, the ring 64 is absent and the wire is attached directly to at least two portions (not shown) of the cylindrical housing portion 61 b.

A sixth embodiment of the irradiation device 70 is shown in fig. 7A, 7B, 7C, and 7D. Fig. 7D is a cross-section taken along line B-B of fig. 7C. The radiation device 70 has a housing 71 composed of an upper housing part 71a and a lower housing part 71b, wherein the upper housing part 71a is similar to the upper housing part 61a of the device 60 of the fifth embodiment. Thus, the upper portion 71a includes a generally frustoconical outer portion 77 with a treatment surface 73 formed by a contact portion 73a and a recessed area within the truncated top of the frustoconical portion 77. The outer portion 77 of the sixth embodiment is shorter than the outer portion 67 of the fifth embodiment, which represents an alternative way of forming the device, and it will be appreciated that both the fifth and sixth embodiments may be adapted to use shorter or longer edges, each having different features and advantages. In a sixth embodiment, a ring 74 is provided in a similar manner to the fourth and fifth embodiments. Alternatively, the loop 74 is absent and the wires are attached directly to at least two portions (not shown) of the lower housing portion 71 b.

The lower cylindrical housing portion 61b of the sixth embodiment is replaced by an alternative lower housing portion 71b, the lower housing portion 71b being in the form of a generally triangular prism having a major axis extending across the diameter of the upper portion 71 a. The triangular prism is configured to accommodate an 1/2 size AA battery placed transversely across the device, rather than being arranged longitudinally in a cylindrical section as in the sixth embodiment. The edges of the prisms are rounded for comfort purposes. The control circuit 79 and the LED lamp system 72 are both located above the battery 78.

As with the fifth embodiment, the sixth embodiment may include a white overmold to direct light to the treatment surface 73.

As mentioned above, for devices for cervical treatment, it is advantageous to provide different sizes, as it allows for an effective treatment of patients with different pregnancy histories. For the fifth and sixth embodiments, these different sizes may be achieved by adjusting the size of the upper portions 61a, 71a, as these portions serve to stabilize the device within the vagina while the treatment surface is placed against the cervix. The lower portions 61b, 71b that house the power supply can be made of a single size, enabling the batteries 68, 78 and the control circuits 69, 79 to use a standardized configuration.

The light-sensitive mixture for photodynamic therapy can be applied to the patient prior to insertion of the device, either directly to the surface of the treatment area, or systemically by intravenous systemic or oral administration. Preferably, the mixture is applied to the treatment surface such that the light-sensitive mixture is applied to the patient during insertion of the device. By using the concave treatment surface embodiment, the photosensitive formulation may be placed within a concave region of a reservoir that provides the formulation. Alternatively, the material of the device may be selected so that the desired photosensitive formulation adheres to the treatment surface to adequately transfer it to the patient, and then the formulation may simply be applied as a layer on the treatment surface. For example, for the device of the fourth embodiment, the formulation may be applied as a layer around the outside of the cylindrical housing.

It will be appreciated that the device of the present invention provides a convenient way for photodynamic therapy in any well of the human or animal body over a prolonged period of time and at a low fluence rate. This increases patient convenience and, in some cases, the efficacy of the treatment.

The above embodiments are merely illustrative and should not limit the scope of protection. Those skilled in the art will appreciate that modifications may be made to these embodiments without departing from the scope of the claims. For example, the housing may be of any shape that allows full and secure insertion into the aperture, and the specific shape of the housing will depend on whether the device is to be used with a human or animal subject and the aperture in which the treatment is to take place. Furthermore, other forms of control circuitry and LED arrays may be used within the present invention.

Claims (17)

1. A radiation apparatus for insertion into a vagina of a patient's body to provide photodynamic therapy to a cervix, the apparatus comprising: a housing surrounding the device and having a size and shape adapted to be fully inserted and secured in the vagina, the housing surrounding an LED lamp system comprising at least one LED, the housing surrounding a power source that powers the LED lamp system, and the housing comprising a treatment surface from which the LED lamp system is configured to emit light when the device is in operation; wherein the treatment surface is at least partially transparent to the light and has a size and/or shape adapted to complementarily match the cervix such that the cervix is illuminated by the light when the apparatus is in operation; and wherein the device operates independently when positioned within the vagina so as not to require a power or light source connected to the outside during operation, wherein the housing comprises a flexible outer portion which, in use, can adjust its shape to form a secure fit within the walls of the vagina, the outer portion extending from the treatment surface to the rear of the device and tapering outwardly so that the widest cross-section of the outer portion is located behind the treatment surface so that the device is adapted to be fully inserted and secured within the vagina.

2. The device of claim 1, wherein the flexible exterior is formed of an elastic material.

3. The device as claimed in claim 1, wherein the treatment surface is formed by a surface of a portion of the material of the housing, wherein an at least partially transparent material is used to form the housing around the LED lamp system and the treatment surface, and wherein the at least partially transparent material is configured to diffuse light emitted from the LED lamp system.

4. The device as claimed in claim 1, comprising a switch for turning on the LED lamp system.

5. The device as claimed in claim 1, wherein the LED lamp system is configured to provide, in use, 1 to 50mW/cm²Light intensity within the range.

6. The device as claimed in claim 5, wherein the LED lamp system is configured to provide 1 to 10mW/cm in use²Light intensity within the range.

7. The device of any preceding claim, wherein at least one LED emits light having a wavelength in the range of 300 and 800 nm.

8. The device as claimed in claim 1, the LED lamp system comprising a control circuit for regulating the radiation provided by the at least one LED.

9. The apparatus of claim 8, wherein the control circuit comprises a receiver for connecting a remote terminal and/or a feedback system and/or one or more performance indicator lights for informing a user whether the apparatus is functioning properly.

10. The apparatus of any of claims 1 to 5, wherein the apparatus further comprises a lens system configured to provide uniform irradiation over a treatment area.

11. The apparatus of claim 10, wherein the treatment surface comprises the lens system.

12. The device of any one of claims 1 to 5, further comprising a drug carrying region for carrying a mixture comprising a photosensitizer or a photosensitizer precursor, said drug carrying region being disposed on said housing.

13. The device of claim 12, wherein the mixture comprises a 5-ALA ester or a pharmaceutically acceptable salt thereof.

14. The device of claim 13, wherein the mixture comprises 5-ALA hexyl ester or a pharmaceutically acceptable salt thereof.

15. The device of claim 12, wherein the drug-carrying region is the treatment surface.

16. The device of any one of claims 1 to 5, wherein the device comprises one or more features that facilitate single use and/or prevent reuse.

17. The device of claim 16, wherein the power source is configured to provide power sufficient for only a single use, and/or the control circuit is configured to prevent reuse by its programmed features, and/or the control circuit includes a disabling mechanism that destroys circuit wiring or software when triggered.