Method for preventing nasolacrimal duct obstruction

Abstract

The invention is directed to a method for preventing nasolacrimal duct obstruction (NLDO) in a patient receiving high dose radioactive iodine for treatment of cancer. The method includes administering an effective amount of perchlorate anion to the eyes of the patient.

Claims

1. A method for reducing formation of fibrosis in at least one nasolacrimal duct of a patient that may occur upon the patient receiving radioactive iodine, the method comprising administering to the patient by topically delivering an ophthalmic composition comprising perchlorate anion to at least one eye of the patient, or instilling the ophthalmic composition directly into the at least one nasolacrimal duct or at least one lacrimal sac of the patient, wherein the perchlorate anion is at a concentration of about 40 mg/ml to about 400 mg/ml and the ophthalmic composition further comprises at least one of white petrolatum, mineral oil, lanolin, or polyethylene mineral oil gel.

2. The method of claim 1, wherein the radioactive iodine is high dose I.sup.113.

3. The method of claim 1, wherein the patient receiving radioactive iodine is receiving the radioactive iodine for treatment of cancer.

4. The method of claim 3, wherein the cancer is head and neck cancer, thyroid cancer, or breast cancer.

5. The method according to claim 1, wherein the patient receiving radioactive iodine is receiving the radioactive iodine to treat a condition selected from the group consisting of Grave's disease, tumor of the pituitary gland, tumor of the testes, tumor of the ovaries, inflammation of the thyroid, and ingestion of excessive amounts of thyroid hormone.

6. The method of claim 1, wherein the patient receiving radioactive iodine is receiving the radioactive iodine for treatment of hyperthyroidism.

7. The method of claim 1, wherein the ophthalmic composition consists essentially of the perchlorate anion and the at least one of white petrolatum, mineral oil, lanolin, or polyethylene mineral oil gel.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) FIG. 1 is a simplified representation of the nasolacrimal system anatomy. Tears are produced in the lacrimal gland 1, flow through ducts 2 leading to the surface of the eyeball 3 and spread over the surface of the eyeball 3. When one blinks, the upper and lower eyelids 4 and 5, push the tears, which also contain proteins and sugars, to the inside corner of the eye. There are two openings at the inside corner of each eye near the nose 13, the superior puncta 6 and inferior puncta 7, which open into the vertical caniculi. The vertical caniculi bend at right angles at the superior ampulla 8 and inferior ampulla 9 and form the horizontal caniculi 10. The horizontal caniculi 10 drain tears and other fluids into the lacrimal sac 11 which is connected with the nasolacrimal duct 12 and which opens into the nose 13.

DETAILED DESCRIPTION OF THE INVENTION

(2) The invention is directed to a method for preventing nasolacrimal duct obstruction (NLDO) in a patient receiving radioactive iodine and especially high dose radioactive iodine for treatment of cancer which comprises administering to each eye of said patient an effective amount of perchlorate anion.

(3) A further embodiment of the invention is directed to a method for preventing nasolacrimal duct obstruction (NLDO) in a patient receiving high dose radioactive iodine (I.sup.131) treatment for thyroid, head and neck and breast cancer which comprises administering to each eye of said patient an effective amount of perchlorate anion, wherein the patient is pre-treated with perchlorate anion for a period of from about 3 to about 5 days prior to initiation of high dose I.sup.131 therapy, wherein treatment with perchlorate anion continues for as long as the patient receives high dose radiation therapy, and wherein treatment with perchlorate anion is continued for from about 3 to about 5 days after cessation of radiation therapy.

(4) The term nasolacrimal duct obstruction (NLDO) as used herein to refer to a blockage in the distal horizontal caniculi 10, lacrimal sac 11 and/or the nasolacrimal duct 12 which prevents liquid from draining into the nose. As a result of the blockage there is a buildup of tears, containing mucin, sugars, and other components such as bacteria in the areas just described leading to irritation and infection.

(5) Symptoms of NLDO are epiphora (excessive tearing) due to a decrease in tear draining, inflammation and infection (dacryocystitis) of the lacrimal sac. The area beneath the eyes next to the nose can become red, inflamed, and sensitive to the touch. The area usually is swollen, and there may be a mucous discharge from the opening of the nasal corner of the eye. Common complaints include itching, irritation, burning, redness, conjunctivitis, and pain.

(6) As used herein, the term high dose radioactive iodine (RAI) refers to cumulative doses of radioactive iodine (I.sup.131) of about 150 mCi or greater. Although iodine can be made into two radioactive isotopes for medical uses, I.sup.123 and I.sup.131, the radiation that I.sup.123 gives off is generally used in scanning or imaging rather than for treatment. The RAI that is most often used in chemotherapy is I.sup.131. It is usually administered to the patient by mouth either as a capsule or a liquid or intravenously (IV). RAI that is not concentrated in tissue is eliminated from the body through sweat and urine.

(7) The term perchlorate anion (CIO4) as used herein refers to the anion which is produced when solid salts of ammonium, potassium, and sodium perchlorate, and perchloric acid are dissolved in an aqueous liquid.

(8) The term effective amount is used herein to mean an amount of perchlorate anion sufficient to reduce or inhibit fibrosis in the distal caniculi, lacrimal sac and/or nasolacrimal duct caused by the concentration of radioactivity by the NIS protein in a patient receiving radioiodine therapy. Any source of perchlorate ion may be used in the method of the invention. However, potassium perchlorate and sodium perchlorate are preferred for use in the methods of the invention because they are in use in other approved pharmaceutical applications and pharmaceutical grade (USP) compound is readily available. Administration of perchlorate anion to the patient should be started from about 3 to 5 days prior to the initiation of I.sup.131 chemotherapy and should continue during the course of chemotherapy and for 3 to 5 days after cessation of I.sup.131 therapy.

(9) Preferred for use in the method of the invention are ophthalmic medicaments containing from about 10 mg/ml to about 500 mg/ml of potassium perchlorate (KCIO.sub.4) or sodium perchlorate (NaCIO.sub.4) and preferably from about 40 mg/ml to about 400 mg/ml and more preferably from about 50 mg/ml to from about 100 mg/ml.

(10) The ophthalmic medicament containing the perchlorate anion is topically administered in the corner of the eye near the superior and inferior puncta 6 and 7. The perchlorate anion may be administered topically to the eye as for example a sterile liquid, e.g., an eye wash or eye drops, an aqueous gel, or ophthalmic ointment or cream. As would be recognized by one skilled in this art, any ophthalmic formulation that is sterile and that is pharmaceutically acceptable, i.e., is safe and effective for its intended purpose may be used to deliver perchlorate anion to the lacrimal sac and nasolacrimal duct.

(11) The maximum volume of the lacrimal sac is about 30 l. The average volume of a human tear is 7 l. Most commercially eye drops have a per drop volume in the range of from 50-75 l. If the droplet volume is much excess of 75 l it probably will not get into the lacrimal sac and thus, the nasolacrimal duct, and the excess solution will be wasted as it drips out of the eye and down the face. Ideally, an eye drop solution will have a high concentration of drug in a minimum drop volume. Multiple drops administered at intervals, produces higher drug concentrations in the lacrimal sac and nasolacrimal duct.

(12) An alternative to a solution of perchlorate anion for use in the methods of the invention is an ophthalmic ointment containing the perchlorate anion. An advantage of an ointment is that it has a longer contact time with the eye and potentially greater total drug bioavailability. Since an ointment can interfere with vision it is best used at bedtime. The perchlorate is added to the ointment base as a solution or a micronized powder. Most ophthalmic ointments are prepared with a base of white petrolatum and mineral oil, often with anhydrous lanolin. Some contain a polyethylene-mineral oil gel. Whatever base is used, it must be nonirritating to the eye, permit diffusion of the drug throughout the eye and retain activity of the perchlorate for a reasonable period of time upon storage.

(13) The ophthalmic medicament containing perchlorate anion may be self-administered or it may be administered by the clinician, in which case it may be instilled directly into the lacrimal sac and nasolacrimal duct.

(14) As would be recognized by one skilled in this art, it is within the skill of the art to prepare sterile, shelf-stable ophthalmic solutions, gels and ointments. See for example, Remington's Pharmaceutical Sciences 18th Ed., Alfonso Gennaro Editor, 1990, Mack Publishing C., Easton, PA 18042, pp. 1581-1595 (now known as Remington: The Science and Practice of Pharmacy, 20th Edition, Alfonso Gennaro Editor, Lippincott Williams & Wilkins, Baltimore, MD) for information regarding the properties of, and the preparation of, ophthalmic solutions and ointments.

(15) Both potassium perchlorate and sodium perchlorate are in use to minimize or reduce accumulation of technetium or I.sup.123 in certain tissues in patients undergoing imaging studies. Potassium perchlorate is available from Mallinckrodt Inc., St. Louis, MO. 63134 under the trade name Perchloracap. Perchloracap is supplied for use during diagnostic studies as an opaque gray gelatin capsule for oral administration. Each capsule contains 200 milligrams of potassium perchlorate (KCIO4) mixed with an inert filler. Perchloracap is administered to minimize the accumulation of pertechnetate Tc 99m in the choroid plexus and in the salivary and thyroid glands in patients receiving sodium pertechnetate Tc 99m injection for brain and blood pool imaging and placenta localization.

(16) Sodium perchlorate is manufactured in the United Kingdom by Torbay PMU, a division of the South Devon Healthcare Trust and is available in the U.K. as a 20 mg/ml solution for injection. Sodium Perchlorate Injection is used as a thyroid blocking agent for patients unable to tolerate alternative oral thyroid blocking agents when undergoing studies with radioiodinated radiopharmaceuticals known to de-iodinate in vivo.

(17) Although potassium and sodium perchlorate have been used to block accumulation of technetium 99m and I.sup.123 in the thyroid gland, choroid plexus, and salivary glands there is no recognition in the art that perchlorate may reduce or eliminate fibrosis that can occur in the nasolacrimal area in patients receiving high dose radioiodine for treatment of various cancers.

(18) The invention and the manner and process of making and using it are now described in such full, clear, and concise terms as to enable any person skilled in the art to which it pertains to make and use same. It is to be understood that the forgoing describes preferred embodiments of the present invention and that modifications may be made therein without departing from the spirit or scope of the present invention as set forth in the claims. To particularly point out and distinctly claim the subject matter regarded as the invention, the following claims conclude this specification.