DRUGS & SUPPLEMENTS
TFT is the brand name for TFT (also known as trifluorothymidine, F3TdR,F3T), an antiviral drug for topical treatment of epithelial keratitis caused by herpes simplex virus. The chemical name of TFT is α,α,α -trifluorothymidine; it has the following structural formula:
TFT sterile ophthalmic solution contains 1% TFT in an aqueous solution with acetic acid and sodium acetate (buffers), sodium chloride, and thimerosal 0.001% (added as a preservative). The pH range is 5.5 to 6.0 and osmolality is approximately 283 mOsm.
TFT is a fluorinated pyrimidine nucleoside with in vitro and in vivo activity against herpes simplex virus, types 1 and 2 and vacciniavirus. Some strains of adenovirus are also inhibited in vitro.
TFT is also effective in the treatment of epithelial keratitis that has not responded clinically to the topical administration of idoxuridine or when ocular toxicity or hypersensitivity to idoxuridine has occurred. In a smaller number of patients found to be resistant to topical vidarabine, TFT was also effective.
TFT interferes with DNA synthesis in cultured mammalian cells. However, its antiviral mechanism of action is not completely known.
In vitro perfusion studies on excised rabbit corneas have shown that TFT penetrates the intact cornea as evidenced by recovery of parental drug and its major metabolite, 5-carboxy-2'-deoxyuridine, on the endothelial side of the cornea. Absence of the corneal epithelium enhances the penetration of TFT approximately two-fold.
Intraocular penetration of TFT occurs after topical instillation of TFT into human eyes. Decreased corneal integrity or stromal or uveal inflammation may enhance the penetration of TFT into the aqueous humor. Unlike the results of ocular penetration of TFT in vitro, 5-carboxy-2'-deoxyuridine was not found in detectable concentrations within the aqueous humor of the human eye.
Systemic absorption of TFT following therapeutic dosing with TFT appears to be negligible. No detectable concentrations of TFT or 5-carboxy-2'-deoxyuridine were found in the sera of adult healthy normal subjects who had TFT instilled into their eyes seven times daily for 14 consecutive days.
During a controlled multicenter clinical trial, 92 of 97 (95%) patients (78 of 81 with dendritic and 14 of 16 with geographic ulcers) responded to therapy with TFT as evidenced by complete corneal re-epithelialization within the 14-day therapy period. Fifty-six of 75 (75%) patients (49 of 58 with dendritic and 7 of 17 with geographic ulcers) responded to idoxuridine therapy. The mean time to corneal re-epithelialization for dendritic ulcers (6 days) and geographic ulcers (7 days) was similar for both therapies.
In other clinical studies, TFT was evaluated in the treatment of herpes simplex virus keratitis in patients who were unresponsive or intolerant to the topical administration of idoxuridine or vidarabine. TFT was effective in 138 of 150 (92%) patients (109 of 114 with dendritic and 29 of 36 with geographic ulcers) as evidenced by corneal re-epithelialization. The mean time to corneal re-epithelialization was 6 days for patients with dendritic ulcers and 12 days for patients with geographic ulcers.
The clinical efficacy of TFT in the treatment of stromal keratitis and uveitis due to herpes simplex virus or ophthalmic infections caused by vacciniavirus and adenovirus has not been established by well-controlled clinical trials. TFT has not been shown to be effective in the prophylaxis of herpes simplex virus keratoconjunctivitis and epithelial keratitis by well-controlled clinical trials. TFT is not effective against bacterial, fungal, or chlamydial infections of the cornea or nonviral trophic lesions.
INDICATIONS AND USAGE
TFT Ophthalmic Solution, 1% (trifluridine ophthalmic solution) is indicated for the treatment of primary keratoconjunctivitis and recurrent epithelial keratitis due to herpes simplex virus, types 1 and 2.
TFT Ophthalmic Solution, 1% is contraindicated for patients who develop hypersensitivity reactions or chemical intolerance to TFT.
The recommended dosage and frequency of administration should not be exceeded (see DOSAGE AND ADMINISTRATION ).
TFT Ophthalmic Solution, 1% should be prescribed only for patients who have a clinical diagnosis of herpetic keratitis.
TFT may cause mild local irritation of the conjunctiva and cornea when instilled, but these effects are usually transient.
Although documented in vitro viral resistance to TFT has not been reported following multiple exposures to TFT, the possibility of the development of viral resistance exists.
Carcinogenesis, Mutagenesis, Impairment of Fertility
TFT has been shown to exert mutagenic, DNA-damaging and cell-transforming activities in various standard in vitro test systems, and clastogenic activity in Vicia faba cells. It did not induce chromosome aberrations in bone marrow cells of male or female rats following a single subcutaneous dose of 100 mg/kg, but was weakly positive in female, but not in male, rats following daily subcutaneous administration at 700 mg/kg/day for 5 days.
Although the significance of these test results is not clear or fully understood, there exists the possibility that mutagenic agents may cause genetic damage in humans.
Lifetime carcinogenicity bioassays in rats and mice given daily subcutaneous doses of TFT have been performed. Rats tested at 1.5, 7.5, and 15 mg/kg/day had increased incidences of adenocarcinomas of the intestinal tract and mammary glands, hemangiosarcomas of the spleen and liver, carcinosarcomas of the prostate gland, and granulosa-thecal cell tumors of the ovary. Mice were tested at 1, 5, and 10 mg/kg/day; those given 10 mg/kg/day TFT had significantly increased incidences of adenocarcinomas of the intestinal tract and uterus. Those given 10 mg/kg/day also had a significantly increased incidence of testicular atrophy as compared to vehicle control mice.
TFT was not teratogenic at doses up to 5 mg/kg/day when given subcutaneously to rats and rabbits. However, fetal toxicity consisting of delayed ossification of portions of the skeleton occurred at dose levels of 2.5 and 5 mg/kg/day in rats and at 2.5 mg/kg/day in rabbits. In addition, both 2.5 and 5 mg/kg/day produced fetal death and resorption in rabbits. In both rats and rabbits, 1 mg/kg/day (5 times the estimated human exposure) was a no-effect level. There were no teratogenic or fetotoxic effects after topical application of TFT Ophthalmic Solution, 1% (approximately 5 times the estimated human exposure) to the eyes of rabbits on the 6th through the 18th days of pregnancy. In a non-standard test, TFT solution has been shown to be teratogenic when injected directly into the yolk sac of chicken eggs. There are no adequate and well-controlled studies in pregnant women. TFT Ophthalmic Solution, 1% should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
It is unlikely that TFT is excreted in human milk after ophthalmic instillation of TFT because of the relatively small dosage (≤5 mg/day), its dilution in body fluids and its extremely short half-life (approximately 12 minutes). The drug should not be prescribed for nursing mothers unless the potential benefits outweigh the potential risks.
Safety and effectiveness in pediatric patients below six years of age have not been established.
No overall clinical differences in safety or effectiveness have been observed between elderly and other adult patients.
The most frequent adverse reactions reported during controlled clinical trials were mild, transient burning or stinging upon instillation (4.6%) and palpebral edema (2.8%). Other adverse reactions in decreasing order of reported frequency were superficial punctate keratopathy, epithelial keratopathy, hypersensitivity reaction, stromal edema, irritation, keratitis sicca, hyperemia, and increased intraocular pressure.
Overdosage by ocular instillation is unlikely because any excess solution should be quickly expelled from the conjunctival sac.
Acute overdosage by accidental oral ingestion of TFT has not occurred. However, should such ingestion occur, the 75 mg dosage of TFT in a 7.5 mL bottle of TFT is not likely to produce adverse effects. Single intravenous doses of 1.5 to 30 mg/kg/day in children and adults with neoplastic disease produce reversible bone marrow depression as the only potentially serious toxic effect and only after three to five courses of therapy. The acute oral LD50 in the mouse and rat was 4379 mg/kg or higher.
DOSAGE AND ADMINISTRATION
Instill one drop of TFT Ophthalmic Solution, 1% onto the cornea of the affected eye every 2 hours while awake for a maximum daily dosage of nine drops until the corneal ulcer has completely re-epithelialized. Following re-epithelialization, treatment for an additional 7 days of one drop every 4 hours while awake for a minimum daily dosage of five drops is recommended.
If there are no signs of improvement after 7 days of therapy or complete re-epithelialization has not occurred after 14 days of therapy, other forms of therapy should be considered. Continuous administration of TFT for periods exceeding 21 days should be avoided because of potential ocular toxicity.
TFT Ophthalmic Solution, 1% is supplied as a sterile ophthalmic solution in a plastic Drop Dose® dispenser bottle of 7.5 mL (NDC 61570-037-75).
Store under refrigeration 2° to 8°C (36° to 46°F).
ANIMAL PHARMACOLOGY AND ANIMAL TOXICOLOGY
Corneal wound healing studies in rabbits showed that TFT did not significantly retard closure of epithelial wounds. However, mild toxic changes such as intracellular edema of the basal cell layer, mild thinning of the overlying epithelium and reduced strength of stromal wounds were observed.
Whereas instillation of TFT into rabbit eyes during a subchronic toxicity study produced some degree of corneal epithelial thinning, a 12-month chronic toxicity study in rabbits in which TFT was instilled into eyes in intermittent, multiple, full-therapy courses showed no drug-related changes in the cornea.
TFT ® OPHTHALMIC SOLUTION, 1%
(trifluridine ophthalmic solution)
STORE UNDER REFRIGERATION 2° to 8°C (36° to 46°F).
Distributed by: Monarch
Pharmaceuticals, Inc., Bristol, TN 37620
Manufactured by: DSM Pharmaceuticals, Inc.,
Greenville, NC 27834
TFT pharmaceutical active ingredients containing related brand and generic drugs:
Active ingredient is the part of the drug or medicine which is biologically active. This portion of the drug is responsible for the main action of the drug which is intended to cure or reduce the symptom or disease. The other portions of the drug which are inactive are called excipients; there role is to act as vehicle or binder. In contrast to active ingredient, the inactive ingredient's role is not significant in the cure or treatment of the disease. There can be one or more active ingredients in a drug.
TFT available forms, composition, doses:
Form of the medicine is the form in which the medicine is marketed in the market, for example, a medicine X can be in the form of capsule or the form of chewable tablet or the form of tablet. Sometimes same medicine can be available as injection form. Each medicine cannot be in all forms but can be marketed in 1, 2, or 3 forms which the pharmaceutical company decided based on various background research results.
Composition is the list of ingredients which combinedly form a medicine. Both active ingredients and inactive ingredients form the composition. The active ingredient gives the desired therapeutic effect whereas the inactive ingredient helps in making the medicine stable.
Doses are various strengths of the medicine like 10mg, 20mg, 30mg and so on. Each medicine comes in various doses which is decided by the manufacturer, that is, pharmaceutical company. The dose is decided on the severity of the symptom or disease.
TFT destination | category:
Destination is defined as the organism to which the drug or medicine is targeted. For most of the drugs what we discuss, human is the drug destination.
Drug category can be defined as major classification of the drug. For example, an antihistaminic or an antipyretic or anti anginal or pain killer, anti-inflammatory or so.
TFT Anatomical Therapeutic Chemical codes:
A medicine is classified depending on the organ or system it acts [Anatomical], based on what result it gives on what disease, symptom [Therapeutical], based on chemical composition [Chemical]. It is called as ATC code. The code is based on Active ingredients of the medicine. A medicine can have different codes as sometimes it acts on different organs for different indications. Same way, different brands with same active ingredients and same indications can have same ATC code.
TFT pharmaceutical companies:
Pharmaceutical companies are drug manufacturing companies that help in complete development of the drug from the background research to formation, clinical trials, release of the drug into the market and marketing of the drug.
Researchers are the persons who are responsible for the scientific research and is responsible for all the background clinical trials that resulted in the development of the drug.
Frequently asked QuestionsCan i drive or operate heavy machine after consuming TFT?
Depending on the reaction of the TFT after taken, if you are feeling dizziness, drowsiness or any weakness as a reaction on your body, Then consider TFT not safe to drive or operate heavy machine after consumption. Meaning that, do not drive or operate heavy duty machines after taking the capsule if the capsule has a strange reaction on your body like dizziness, drowsiness. As prescribed by a pharmacist, it is dangerous to take alcohol while taking medicines as it exposed patients to drowsiness and health risk. Please take note of such effect most especially when taking Primosa capsule. It's advisable to consult your doctor on time for a proper recommendation and medical consultations.Is TFT addictive or habit forming?
Medicines are not designed with the mind of creating an addiction or abuse on the health of the users. Addictive Medicine is categorically called Controlled substances by the government. For instance, Schedule H or X in India and schedule II-V in the US are controlled substances.
Please consult the medicine instruction manual on how to use and ensure it is not a controlled substance.In conclusion, self medication is a killer to your health. Consult your doctor for a proper prescription, recommendation, and guidiance.
Reviewsdrugs.com conducted a study on TFT, and the result of the survey is set out below. It is noteworthy that the product of the survey is based on the perception and impressions of the visitors of the website as well as the views of TFT consumers. We, as a result of this, advice that you do not base your therapeutic or medical decisions on this result, but rather consult your certified medical experts for their recommendations.
Visitor reported usefulNo survey data has been collected yet
Visitor reported side effectsNo survey data has been collected yet
One visitor reported price estimatesWhat is your opinion about drug cost? Did you feel the cost is apt, or did you feel it is expensive?
The report given by the sdrugs.com website users shows the following figures about several people who felt the medicine TFT is expensive, and the medicine is not expensive. The results are mixed. The perception of the cost of the medicine to be expensive or not depends on the brand name of the medicine, country, and place where it is sold, and the affordability of the patient. You can choose a generic drug in the place of the branded drug to save the cost. The efficiency of the medicine will not vary if it is generic or a branded one.
One visitor reported frequency of useHow often in a day do you take the medicine?
Are you taking the TFT drug as prescribed by the doctor?
Few medications can be taken 4 times in a day more than prescribed when the doctor's advice mentions the medicine can be taken according to frequency or severity of symptoms. Most times, be very careful and clear about the number of times you are taking the medication. The report of sdrugs.com website users about the frequency of taking the drug TFT is mentioned below.
Visitor reported dosesNo survey data has been collected yet
Visitor reported time for resultsNo survey data has been collected yet
Visitor reported administrationNo survey data has been collected yet
Visitor reported ageNo survey data has been collected yet
The information was verified by Dr. Arunabha Ray, MD Pharmacology