In 2001, the US Food and Drug Administration approved a novel HIV medicine known as tenofovir disoproxil fumarate (TDF). The decision was praised by patient activists, who pointed out that it marked the approval of the first innovative antiviral drug after the FDA rejected a comparable medication two years prior. However, significant transformations occur over ten years.
Patient Advocates Express Concern Over Gilead’s Marketing Plans for Tenofovir Alafenamide (TAF)
Firstly, Gilead Sciences, the manufacturer of TDF, located in Foster City, California, has developed a more recent and improved version of tenofovir known as tenofovir alafenamide (TAF). Meanwhile, patient advocates at the International AIDS Society Conference in Kuala Lumpur this week are expressing their dissatisfaction that the business is not developing a separate version of TAF and intends to market it exclusively in costly combination pills.
Currently, Gilead offers TDF as a standalone formulation, which is offered under the brand name Viread. It is also accessible as a component of Stribild, a combination pill that contains the medications elvitegravir, cobicistat, and emtricitabine. The World Health Organization has approved these four drugs as the preferred treatment for initial therapy. Tenofovir alafenamide (TAF) is currently being developed in three different combination pills.
It is being formulated as a dual-drug tablet with emtricitabine. Additionally, TAF is being used as a substitute for tenofovir disoproxil fumarate (TDF) in the existing ‘quad’ pill. Furthermore, TAF is being included in a new single-pill treatment that also contains darunavir, cobicistat, and emtricitabine.
Pushing for Affordable Healthcare: Advocates Rally for Independent TAF Medication
In the absence of a separate version of TAF, health programs in economically disadvantaged regions are unable to integrate it with more affordable alternatives, like as lamivudine. Lamivudine functions similarly to emtricitabine but is priced at around half the cost, amounting to $37 for a year of therapy.
An appeal was made to Gilead Sciences on June 13th by a letter containing nearly 300 signatures from advocates worldwide, including prominent groups such as the New York-based Treatment Action Group, HIV i-Base in the UK, and San Francisco’s Project Inform. The letter urged Gilead Sciences to prioritize the development of TAF as an independent medication.
“Combining TAF with other brand-name drugs in the US would probably limit our ability to take advantage of TAF’s potential for increased safety when used with generic drugs, which could help reduce annual treatment expenses,” explains Tim Horn, HIV project director at the Treatment Action Group.
If Gilead decides to license TAF with the Medicines Patent Pool, a stand-alone version of TAF might be developed, allowing generic versions of the drug to be produced. This would be especially beneficial for populations in resource-limited nations.
An enhancement
TAF Emerges as a Promising Advance in HIV Treatment: Superior Efficacy and Reduced Side Effects
There is a significant amount at risk. Both TDF and TAF are classified as nucleotide reverse transcriptase inhibitors (NRTIs), which impede the replication of HIV within immune cells. However, initial investigations indicate that the latter option is a significant improvement. Research indicates that a dosage of 25 milligrams of TAF was more effective than a dosage of 300 milligrams of TDF, resulting in a tissue concentration of TDF that was seven times higher.
This was observed during testing of the four-drug ‘quad’ combination. TAF showed a reduced incidence of adverse effects on renal function and bone mineral density. Furthermore, the current study indicates that TAF has the potential to be effective against HIV strains that are resistant to TDF and other NRTIs.
Cara Miller, a spokesman for Gilead, stated to Nature Medicine that the business prioritizes the development of new HIV regimens in the form of single-tablet medications, which may include TAF. However, the company’s drug research pipeline solely includes solo-drug formulations of TAF for phase 1 investigations on chronic hepatitis B virus infections. Miller currently lacks additional details regarding the development of TAF.
The Costly Impact of Patented AIDS Drug Combinations on Accessibility and Patient Survival
“The implementation of a fixed-dose combination is desired due to its ability to enhance compliance among individuals,” states Kate Krauss, the executive director of the AIDS Policy Project in Philadelphia. However, if the only option accessible is a patented fixed-drug combination, the exorbitant cost will render it unaffordable for millions of individuals.
“It will not be possible to create other life-saving combinations of AIDS drugs using a Gilead drug with cheaper generic alternatives,” Krauss states. “When patients exhaust effective drug combinations, their time is limited.”
