The Challenge of ARV Resistance. 1/12/09

Experience from other countries shows that not everyone will respond well to the same antiretroviral drugs. Some will improve, others will not. Those who fail on one or more group of drugs need a replacement. But the current pool of ARV drugs in the public sector offers no alternative.

People who rely on the public health sector for their antiretroviral medication.  Currently, they have zero options available to them should they develop resistance or experience unbearable side-effects to the current drugs offered by the government. Since the rollout of antiretroviral treatment in 2003, government has not added any new drugs to the current first and second line treatment. This is despite the fact that new drugs have been licensed for use in the country. With no replacement drugs, people are most likely to die.        

“It’s a pity because there are a range of new drugs available that have come onto the market only in the last three years… unfortunately in the developed countries and, increasingly, in the private sector here in South Africa. No one needs to die of resistance or of toxicity. They should be able to access safer drugs. The problem is that these drugs are often very expensive. We certainly need them in the state sector in a far broader way. People who fail second line have no options available to them currently in the state sector”, says Professor Francois Venter, head of the Southern African HIV/AIDS Clinicians’ Society.

Over 800 000 South Africans are now on ARVs in the government sector and observational studies in Cape Town and Johannesburg show that a few thousand are resistant to the first line regimen. Others cannot tolerate the second line regimen because of side-effects. 

“There is good data from Cape Town suggesting between 3% - 4% fail per year… the first line regimen. That’s probably the same for our programmes here in Johannesburg and from what I’ve seen… some of the more rural areas. The problem is that we have so many patients on treatment now that 3% or 4% actually translates, in absolute numbers, into a large number of people. So, there are probably a couple of thousands in the country at the moment who have failed first line therapy and probably a thousand or two thousand who are failing the second line therapy. And those ones failing second line therapy are really hard to manage… to try and get to the bottom of. We try and work out why they are not swallowing their tablets, what’s going on in their lives. But if it’s because of toxicity, your back is a bit against the wall because we don’t have anything to substitute it with”, says Venter.

Until recently, new drugs have been available only in developed countries. But after licensure by the country’s medicines regulatory authority, the Medicines Control Council, some of the new drugs are available in South Africa. However, the choices come at a steep price.

“The cheapest of the drugs cost R1 000 – R2 000 a month and some of them can be R5 000 – R6 000 a month. That’s a lot of money, especially when you think that’s going to go on forever if they take those drugs”, Venter says.

Some are lucky to have doctors refer them to research centres to participate in new drug trials. But others die without any intervention. The one way to bring costs down is to allow for generic manufacturing of the drugs. But negotiations could take long. Meanwhile, according to the National Strategic Plan on HIV/AIDS, two million people should be on treatment by 2011. Reaching those people could prove problematic if the issue of drug resistance and toxicity is not addressed. In addition, the Department of Health is expected to expand treatment eligibility in line with the new World Health Organisation protocol.

“We know, medically, that you should start patients earlier, on a higher CD4 count if you want to prevent people from getting TB infections (and) more costly and difficult care later. There’s a revision of the standards by the WHO right now and we expect that if the treatment initiation standard is changed, we might have probably, at least, a doubling of the number of people in need of treatment today”, explains Dr Tido von Schoen-Angerer, head of Medecins Sans Frontiere’s Campaign for Access to Essential Medicines.

Head of the South African National AIDS Council (SANAC), Dr Nono Simelela, said “the issue needs to be addressed in order to maintain the successes made in AIDS treatment”.

Simelela said “an audit needs to be done to determine the number of people who have developed resistance and need third-line treatment; and how much it will cost the government to secure them alternative treatment”.