The HIV market is expected to undergo significant changes in the next few years, with older drugs being replaced by new treatments in a move that will see GlaxoSmithKline’s “ long reign as the undisputed king of the HIV treatment market come to an end”, says a new study.

Consultancy firm Datamonitor says that the HIV market generated sales of about $8 billion in 2006 in the major markets and despite the fact that 65% of the currently marketed treatments are expected to lose patent protection in the next five to 10 years, newer treatments will push HIV sales up to $11.5 billion by 2016. As for GSK, although it currently has eight marketed products, “the majority are relatively old and at least five of them are expected to lose patent protection by 2014”, claims Datamonitor infectious diseases analyst Mansi Shah. She added that “as a result, GSK’s market share may be drastically reduced by 2016 if it does not find successful new products.”

Now, “new products will reshape established treatment paradigms”, the study notes, and the reformulation of existing drugs into fixed-dose combinations such as Merck& Co’s Atripla, a once-daily, triple therapy that is delivered in a single tablet and combines Bristol-Myers Squibb's Sustiva (efavirenz) and Gilead's Emtriva (emtricitabine) and Viread (tenofovir), plus increased availability of once-daily therapies such as Abbott’s Kaletra (lopinavir/ritonavir) and BMS’ Reyataz (atazanavir) have simplified early lines of treatment . Such therapies have more convenient dosing schedules and have a significantly reduced pill burden, thereby improving the quality of life for patients, notes Datamonitor.

Growth will also be driven by Tibotec/Johnson & Johnson’s new generation protease inhibitor Prezista (darunavir) and the new class of drugs such as Pfizer’s Celsentri (maraviroc), the first CCR5 inhibitor, and Merck & Co’s integrase inhibitor Isentress (raltegravir). Other developmental drugs from these classes include Schering-Plough’s CCR5 inhibitor vicriviroc in Phase III and Gilead’s integrase inhibitor elivitegravir (GS-9137) (Phase II). Ms Shah also mentioned two other Phase II drugs – Panacos’ maturation inhibitor bevirimat and Tanox’s CD-4 receptor inhibitor TNX-355.

She concluded by saying that while the patent expiry of “many of the currently efficacious and financially successful drugs is bad news for drugs developers, the good news for HIV patients is that there are a number of novel and very promising treatments in the development pipeline”.