This week, the US Food and Drug Administration (FDA) announced its approval of dolutegravir, a new HIV medicine made by ViiV, a joint venture between pharmaceutical giants Pfizer and GlaxoSmithKlein and Japanese company Shionogi. It will be sold under the brand name Tivicay. The drug forms part of a class of antiretroviral drugs (ARVs) called integrase inhibitors, which work by interfering with one of the enzymes the HI-virus needs to multiply.
The FDA says that a 50mg dose of the drug should be taken once or twice daily, with or without food, and can be used in patients who have never been treated before, as well as those who have developed resistance to other ARVs. It can also be used in children over the age of 12 who weigh 40kgs or more. According to Médecins Sans Frontières (MSF), the drug will likely be used as a first-line HIV drug (the most effective treatment with the fewest side effects) in the developed world. The Treatment Action Campaign said dolutegravir “could potentially become a vital drug in the global struggle against HIV”.
But in a statement released Tuesday, MSF warned that dolutegravir may not be easily available in poorer countries. While David Daley, spokesperson for GlaxoSmithKline, says that ViiV grants voluntary licenses to some generic companies, allowing them to produce cheaper versions of their patented products, these licenses only allow countries that are considered low-income or least-developed, or located within sub-Saharan Africa, to access the cheaper drugs.
Middle-income countries, on the other hand, are subject to “tiered-pricing” of the patented product, with prices set on a sliding scale depending on a country’s gross domestic product and disease burden. As such, MSF says that some may be unable to afford the drug. “We are deeply concerned that ViiV’s business strategy will result in dolutegravir being priced out of reach in countries excluded from ViiV’s licensing deals,” says Rohit Malpani, director of policy and analysis at MSF’s Access Campaign. “We have seen in the past excluded countries are left paying exorbitant prices.”
As it is located in sub-Saharan African, South Africa will be able to source a generic version of dolutegravir after a voluntary license agreement is concluded between ViiV and a generic company, according to Daley. He said that ViiV submitted an application to register dolutegravir in South Africa with the country’s Medicines Control Council in June of this year, but could not offer an estimation of its price pending registration. According to the Treatment Action Campaign, the drug could be available for as little as R300 per patient per year, but only if multiple generic versions are made. Voluntary licenses often only allow one producer to make a generic version of a product, and limit where these versions can be sold.
Francois Venter, deputy executive director at the Reproductive Health and HIV Institute at the University of the Witwatersrand, expects dolutegravir to hit the South African market in one to two years. Calling it “amazingly side-effect free in the short to medium term”, he said that it could be used instead of efavirenz, which has some side effects and is currently used in first-line therapy. Most efavirenz side effects occur in the brain, and result in dizziness, poor sleep, confusion, and abnormal thinking, among others, according to the online HIV information source, Aidsmap.com.
In studies, dolutegravir has been shown to be more effective than raltegravir, a competitor integrase inhibitor, when treating patients who have already been on ARVs. According to Treatment Action Campaign, raltegravir is currently used in third-line treatment in South Africa, which is used when patients develop resistance to other ARVs. While developed countries will likely use dolutegravir in first-line, it may be unaffordable for South Africa to do so. Venter said South Africa would likely look at data stemming from other countries who use dolutegravir to inform those using it here.