Latest research on Tenofovir

Tenofovir disoproxil fumarate (a prodrug of tenofovir), marketed by Gilead Sciences under the trade name Viread®, belongs to a class of antiretroviral drugs known as nucleotide analogue reverse transcriptase inhibitors (nRTIs), which block reverse transcriptase, an enzyme crucial to viral production in HIV-infected people. [Wikipedia] In vivo tenofovir disoproxil fumarate is converted to tenofovir, an acyclic nucleoside phosphonate (nucleotide) analog of adenosine 5'-monophosphate.

Tenofovir dosage

The first-line regimen was preferably a fixed-dose combination of Tenofovir disoproxil fumarate (TDF) 300 mg and Emtricitabine (FTC) 250 mg (Truvada®, Gilead) plus Efavirenz (EFV) 600 mg (Stocrin®, MSD). [source, 2016]
Given access to all available drugs, more than three-quarters of doctors would use the WHO recommended first line fixed dose combination of Tenofovir (TDF), Emtricitabine (or the equivalent analogue, Lamivudine) and Efavirenz (EFV) for themselves, suggesting high confidence in the efficacy and side effect profile of the combination. [source, 2016]
In a large Phase IIb study, 280 patients with documented resistance to Lamivudine were randomized to either Tenofovir monotherapy or the fixed-dose combination of Tenofovir plus Emtricitabine (an l-nucleoside analogue similar to Lamivudine) for 96 weeks [198]. [source, 2015]
In the first studies in healthy volunteers, the pharmacokinetic parameters of elvitegravir following administration of a fixed-dose combination with elvitegravir, Emtricitabine, Tenofovir disoproxil fumarate (DF), and cobicistat were similar to those of ritonavir-boosted elvitegravir. [source, 2015]
As a result, the US Department of Health and Human Services (DHHS), German, Spanish, and Italian HIV treatment guidelines have been updated to include dolutegravir as a preferred first-line third agent in combination with preferred fixed-dose, dual-combination (FDC) backbones, abacavir/lamivudine, or Tenofovir disoproxil fumarate/emtricitabine [10]. [source, 2015]
A diagnosis of lichenoid drug eruption secondary to Tenofovir was made and the patient was started on oral corticosteroids at a dose of 30 mg/day of Prednisolone along with topical corticosteroids (Mometasone Furoate 0.1% cream twice daily), emollients and oral anti-histamines. [source, 2015]
Moreover, hair concentrations of Tenofovir (TFV) are strongly and linearly related to dose.34 [source, 2015]
Orally delivered Truvada (a fixed dose combination of Emtricitabine and Tenofovir disoproxil fumarate) has been approved by the Food and Drug Administration for pre-exposure prophylaxis against HIV infection. [source, 2015]
But TAF is a much more potent prodrug than TDF: At a dose less than one-tenth of TDF, TAF produces intracellular levels of the active metabolite Tenofovir diphosphate that are sevenfold higher. [source, 2015]
However, since the patient did not achieve adequate viral suppression with Entecavir at doses recommended in the setting of Lamivudine resistance and due to lack of safer alternatives, Tenofovir disoproxil fumarate was added to Entecavir, with close monitoring of serum creatinine and tubular function. [source, 2015]