1. Indications and Usage
\nTreatment of Chronic Hepatitis B Virus (HBV) Infection:
\nIndicated for the treatment of chronic hepatitis B virus (HBV) infection in adults and adolescents (aged 12 years and older, weighing at least 35 kg).
\n2. Dosage and Administration
\nRecommended Dosage:
\nAdults and Adolescents (\u226512 years and \u226535 kg): 25 mg tablet, orally, once daily with food.
\nAdults with Severe Renal Impairment (CrCl < 30 mL\/min) or End-Stage Renal Disease (ESRD):Dosage adjustment is not required.
\nAdministration Instructions:
\nMust be taken with food to ensure adequate bioavailability.
\nDo not administer to patients with unknown or undiagnosed liver disease without confirming HBV status.
\nMissed Dose:
\nIf a dose is missed and it is less than 18 hours since the usual time of dosing, take the dose as soon as possible with food and resume the normal schedule.
\nIf more than 18 hours have passed, skip the missed dose and resume the normal schedule.
\n3. Mechanism of Action
\nNucleotide Analog Reverse Transcriptase Inhibitor (NRTI):
\nTenofovir alafenamide (TAF) is a nucleotide analog reverse transcriptase inhibitor.
\nPathway:
\nTAF is a prodrug of tenofovir. It is more stable in plasma than tenofovir disoproxil fumarate (TDF) and is efficiently taken up by hepatocytes (liver cells).
\nPhysiological Effect:
\nInside the cell, TAF is hydrolyzed to tenofovir, which is then phosphorylated to the active metabolite, tenofovir-diphosphate.
\nTenofovir-diphosphate inhibits HBV polymerase (reverse transcriptase) by competing with the natural substrate (deoxyadenosine 5\u2032-triphosphate) and incorporating into viral DNA, resulting in DNA chain termination.
\n4. Safety and Warnings
\nHepatitis B Exacerbations:
\nSevere acute exacerbations of hepatitis B have been reported in patients who have discontinued anti-hepatitis B therapy, including TAF. Hepatic function should be monitored closely for at least several months after stopping treatment.
\nRenal Impairment:
\nAlthough TAF has a lower risk of renal toxicity compared to TDF, renal impairment (including acute renal failure and Fanconi syndrome) has been reported. Monitor creatinine clearance (CrCl) and urine glucose in patients with renal risk factors.
\nBone Toxicity:
\nTAF has a lower risk of bone toxicity compared to TDF, but decreases in bone mineral density (BMD) have been observed.
\nImmune Reconstitution Syndrome:
\nIn patients coinfected with HIV-1 and HBV, the possibility of immune reconstitution syndrome should be considered when anti-HBV therapy is initiated.
\n5. Adverse Reactions
\nMost Common:
\nHeadache (12%), fatigue (6%), and nausea (6%).
\nOther:
\nDiarrhea, abdominal pain, dyspepsia, rash, and pruritus.
\n6. Drug Interactions
\nP-glycoprotein (P-gp) Inducers:
\nDrugs that induce P-gp (e.g., rifampin, carbamazepine, phenytoin) may significantly decrease plasma concentrations of TAF, leading to loss of therapeutic effect. Concomitant use is not recommended.
\nDrugs that Increase Renal Proximal Tubule Transport:
\nConcomitant use with drugs that compete for renal transport (e.g., cobicistat, ritonavir, lopinavir\/ritonavir) may increase TAF plasma concentrations and the risk of adverse reactions.
\nAntacids:
\nConcomitant use with antacids containing aluminum, magnesium, or calcium may reduce TAF absorption.
\n7. Pharmaceutical Information
\nChemical Name:
\nPropan-2-yl (S)-((S)-(((2R)-1-(6-amino-9H-purin-9-yl)propan-2-yl)oxy)methyl)(phenoxy)phosphoryl)amino)butanoate fumarate.
\nMolecular Formula:
\nC21H29N6O5P\u00b7C4H4O4.
\nStorage:
\nStore at 25\u00b0C (77\u00b0F); excursions permitted to 15-30\u00b0C (59-86\u00b0F). Protect from moisture.<\/p>\n","protected":false},"excerpt":{"rendered":"
Brand Name: \u97e6\u7acb\u5f97\u00ae (Vemlidy\u00ae)
\nGeneric Name: Tenofovir Alafenamide Fumarate
\nStrength: 25 mg per tablet, 30 tablets per bottle
\nManufacturer: Patheon Inc.
\nMarketing Authorization Holder: Gilead Sciences, Inc.
\nApproval Date in China: November 8, 2018
\nRegistration Number: \u56fd\u836f\u51c6\u5b57 HJ20180060
\nStorage: Store below 30\u2103, keep sealed and away from moisture; keep out of sight and reach of children<\/p>\n
Price&Cost:Contact Us now for the best price of Tenofovir Alafenamide Fumarate\uff08Vemlidy\uff09<\/p>\n","protected":false},"featured_media":3097,"comment_status":"open","ping_status":"closed","template":"","meta":[],"product_brand":[],"product_cat":[27],"product_tag":[],"class_list":["post-3093","product","type-product","status-publish","has-post-thumbnail","product_cat-tablets","first","instock","shipping-taxable","product-type-simple"],"yoast_head":"\n