Taficita (Tenofovir Alafenamide & Emtricitabine)

DESCRIPTION

Classification: Anti-retroviral drug TAF and Emtricitabine are nucleotide reverse transcriptase inhibitor that involved in suppression of growth of HIV virus associated with AIDS

Taficita   is a fixed dose combination drug, which contains two excellent components like tenofovir Alafenamide fumarate and Emtricitabine Taficita   is a prescription medicine, used by the patients only under the knowledge of medical practitioner

INDICATION

Taficita   , a combination tablet contains tenofovir Alafenamide fumarate and Emtricitabine is mainly indicated for the treatment of HIV-1 infection in adult’s patients.

MECHANISM OF ACTION

TAF

TAF is a novel ester prodrug of anti-retroviral tenofovir, and it is a nucleotide reverse transcriptase inhibitor After an oral administration, TAF is transformed into tenofovir Tenofovir (acyclic nucleoside phosphonate analog of adenosine 5 monophosphate) Tenofovir depletes DNA binding, there is a lack of 3 OH molecules (water molecules are responsible for phosphodiester bond linkage) By opposing the regular nucleotide for insertion into proviral DNA and blockade of formation of 5 to 3 phosphodiester linkage which is needed for DNA elongation Tenofovir leads to chain termination and block proviral DNA transcription

Emtricitabine

Emtricitabine is one of the components of Taficita  ; it exhibits its anti-retroviral activity by inhibiting reverse transcriptase, the enzyme which is responsible for transcript HIV RNA into new viral DNA. Emtricitabine is phosphorylated to Emtricitabine 5 phosphate with the help of cellular enzymes Emtricitabine 5 phosphates is HIV-1 reverse transcriptase inhibitor Emtricitabine 5 phosphates fight with deoxycytidine 5 triphosphate (natural substrate) and inserted into viral DNA causes chain termination

ADME PROPERTIES

ABSORPTION

Taficita   ; the absorption of tenofovir is occur fastly and its Tmax is observed at 1 hour after administration; whereas Emtricitabine is absorbed rapidly and its mean bioavailability is 93%

DISTRIBUTION

The human plasma protein bound of Emtricitabine is very low less than 4% Tenofovir is highly bound to human plasma protein with the range of 80%

METABOLISM

TAF, is hydrolyzed into tenofovir within the cells, it is the major metabolite again phosphorylated into tenofovir diphosphate active metabolite Emtricitabine is metabolized minimally and it is found in urine as unchanged form

EXCRETION

The route of elimination mostly through urine The terminal half life of Emtricitabine is 10 hours The terminal half life period of tenofovir is 0.51 hour

DOSAGE MANAGEMENT

DOSAGE AND ADMINISTRATION

The prescribed dose of Taficita   in the condition of HIV-1 infection in adults is, one tablet should be taken once daily with or without food. In Pre-exposure Prophylaxis: uninfected adults should take one tablet orally as a single dose.

SIDE EFFECTS
GENERAL
Diarrhea, nausea, fatigue, headache, dizziness, depression, insomnia, abnormal drms

METABOLIC
Increased fasting cholesterol, decreased phosphorus, increased fasting triglycerides, altered serum glucose, weight loss, hyperglycemia, increased alkaline phosphatase, lactic acidosis severe hepatomegaly

HEPATIC
Increased AST and ALT, hepatic steatosis, lactic acidosis, increased bilirubin, severe acute exacerbation of hepatitis B

BLOOD
Decreased neutrophils and hemoglobulin

RESPIRATORY
Pharyngitis, sinusitis, upper respiratory tract infection, Nasopharyngitis, increased cough, pneumonia, rhinitis

GASTROINTESTINAL
Increased serum amylase, abdominal pain, pancreatitis, increased serum lipase

PSYCHIATRIC
Depression, insomnia, anxiety

NERVE SYSTEM
Headache, somnolence, peripheral neuropathy

OTHERS
Fatigue, syphilis, pain, fever, asthenia, high vitamin D levels

SKIN
Rashes, skin discoloration, lipodystrophy, angioedema, sweating

GENITOURINARY
Proteinuria, urethritis, urinary tract infection, Hematuria, genital ulceration, anogenital warts Polyuria, glycosuria

IMMUNE
Immune reconstitution/reactivation syndrome, autoimmune disorders

HYPERSENSITIVITY
Allergic reaction

ENDOCRINE
High serum parathyroid hormones

PRECAUTION

Taficita   should be used cautiously, during the therapy some of adverse effects occur; Immune reconstitution syndrome Lactic acidosis Hepatomegaly with steatosis Renal toxicity Acute or severe exacerbations of HBV occurs during discontinuation of anti-retroviral therapy Renal impairment

DRUG INTERACTION

Acyclovir-valaciclovir: increase the serum concentration of tenofovir Adefovir: decrease the therapeutic effect of tenofovir Amino glycosides: increase the serum concentration of tenofovir Carbamazepine: decrease the serum concentration of tenofovir Cidofovir: increase the serum concentration of tenofovir Cobicistat: may increase the toxic effects of tenofovir Diclofenac: may enhance the nephrotoxicity effect of tenofovir Fosphenytoin/phenytoin: decrease the serum concentration of tenofovir Lamivudine: increase toxic effects of Emtricitabine NSAIDS: increase the nephrotoxicity effect of tenofovir Orlistat: decrease the serum concentration of anti-retroviral drugs Oxcarbazepine, Phenobarbital, primidone, rifabutin, rifampin, rifapentine, st. Johns wort, tipranavir these are the drugs which involved in depletion of serum concentration of tenofovir

CONTRAINDICATIONS

Taficita   should not be used in persons with unknown or positive 1 status. Taficita   not used as monotherapy, it is used with other retroviral medicine. Hypersensitivity in lactation .

PREGNANCY & LACTATION

Pregnancy category: B Taficita   should be used cautiously, it is recommended for limited number for pregnancy In case of any deformity, Taficita   should not suggested for pregnancy condition or women who become pregnant Breast feeding is not recommended

STORAGE

Taficita   tablet container should be stored below 30°C (86°F) Container should be keep away from moisture, heat and light

MISSED DOSE

If patient fail to take the dose of Taficita   tablet, must consult with medical practitioner To avoid overdose toxicity problems, skipped the missed dose and follow the regular dosing schedule Do not take double dose