3 min

New anti-HIV pill Odefsey comes to Canada

Gilead’s latest antiretroviral drug claims lower side effects, but what about the cost?

Odefsey is the latest anti-HIV drug from Gilead made with the compound tenofovir alafenamide (TAF), which boasts more efficiency at targeting parts of the body where the drug is most needed. Credit: Courtesy Gilead Sciences

A new antiretroviral drug will soon be available to Canadian HIV patients, but it comes with a dose of controversy and likely a daunting price tag.

Odefsey, the successor to the older Complera, is the latest in Gilead Sciences’ line of anti-HIV drugs. Gilead also makes Truvada to treat HIV and Truvada for PrEP to lower the risk of HIV transmission.

Health Canada gave Odefsey its stamp of approval in February 2017.

Lower side effects, lower doses

The new pill’s advantage is the compound tenofovir alafenamide (TAF), a new means of delivering the drug tenofovir. Compared to the tenofovir disoproxil fumarate (TDF) found in Complera, TAF boasts better “targeting,” delivering the drug efficiently to parts of the body where it is most needed. That means TAF drugs require much lower doses, achieving the same effect while reducing harm to the bones and kidneys.

While Complera packs 300 milligrams of TDF, Odefsey contains only 25 milligrams of TAF. The new drug could be a boon to an aging population of HIV patients, many of whom are taking other medications and are hoping for long golden years on antiretrovirals, free from side effects.

The rollout of Odefsey, however, comes with a big catch: patent law. Odefsey is hitting the market just as Gilead’s patent on TDF drugs is set to expire in December 2017. While the older TDF drugs are likely to plummet in price, Gilead has the patent on TAF locked down until 2022.

The timing is suspicious enough that the San Francisco-based AIDS Healthcare Foundation sued Gilead last year, accusing the company of deliberately delaying the development of TAF to squeeze money out if its customers. The lawsuit failed, but HIV activists have pointed out that the timing is, if not conspiratorial, at least very convenient for Gilead. Activists also point out that Gilead has raised prices on its older drugs, in an apparent bid to convince patients to switch to the new TAF regimes before the company’s patent falls through.

Will provinces pay for Odefsey?

For Canadian provinces, which will soon have to negotiate with Gilead over the price of Odefsey through the pan-Canadian Pharmaceutical Alliance, this raises two important questions: How much more expensive will TAF be than generic TDF, and is it worth paying for?

There’s no question, says Dr Stephen Shafran, a professor of infectious diseases at the University of Alberta, that TAF is the better drug.

“I think any clinician would tell you, if price is not a consideration, why would we use TDF if you have access to TAF?” he says.

Shafran says the most recent research shows TAF beating its forebears for better viral suppression and fewer bone and kidney problems over time. But money, unfortunately, is on the table. He says it’s likely that provinces will decide not to cover TAF for everyone with HIV, and health services or doctors will have to pick and choose which patients get access.

“I’m hoping that government and industry will agree on a price that allows us open access,” Shafran says. “But if they don’t, then it will put us in a position that makes things more complicated.”

In the best case scenario, access to cheap TDF drugs could drag down the price of TAF, and make it accessible to all. In the worst, TAF could remain a luxury for those with gold-plated insurance.

Is a new antiretroviral drug really necessary?

Dr Julio Montaner, director of the BC Centre for Excellence in HIV/AIDS, says not all patients need TAF. The existing drugs already work perfectly well for nearly all patients, he says, and when rare side effects do appear, they are easy to detect. Unlike the switch from first to second generation drugs in the early 2000s — when the newer drug could mean freedom from crippling side effects and disease — the marginal differences between second and third generation drugs are slender.

“The current treatments we have available are operating at a very high level of performance,” Montaner says. “We have the Cadillac of a treatment available. The question now is, is a Ferrari needed in every instance?”

Montaner says he is confident the BC government will cover TAF drugs for the few patients who need them. In most cases, however, generic TDF drugs will do just fine.

“The question is, how do we create a system that’s best for the patients, and not get distracted by the hype that the pharmaceutical industry is creating about every single new molecule,” he says. “What problem are we trying to solve here? Is there a clinical problem? Because I haven’t seen it. Or are we trying to solve a problem of income for the pharmaceutical industry?”

Odefsey is not the first TAF drug from Gilead to arrive in Canada; the single pill regimen Genvoya was approved in 2015.

Price and access have also been key issues for Canadians trying to take Gilead’s TDF-based drug Truvada, which is used for pre-exposure prophylaxis (PrEP). Since PrEP drugs were approved in Canada, they have commonly been accessible only to people on certain medical insurance plans, or to those who bring generics semi-legally across the border.