TB breakthrough a challenge to govt
South African researchers have shown that deaths among people co-infected with HIV and TB could be more than halved by starting antiretroviral therapy earlier, adding further pressure on government to improve treatment for both diseases.
If the government adapts its treatment guidelines in line with the findings—which were so dramatic that the clinical trial was stopped early on ethical grounds—it will mean starting 150 000 people living with TB on anti-HIV medicine much earlier than has been planned, and budgeted, for.
Professor Salim Abdool Karim, who headed the study, said the research indicated that up to 10 000 lives a year could be saved if people with TB were given antiretrovirals at the beginning of the TB treatment if they had a CD4 count of less than 500.
Currently the guidelines are for HIV-positive people to start ARVs when their CD4 count drops to 200, or when this is clinically indicated.
Typically the policy has been for people to start ARVs only once they have completed TB treatment, because of fears of interactions between the two sets of drugs.
One of the key anti-TB drugs, rifampicin, increases the speed at which one class of ARVs is broken down by the body. The result is a need to adjust the ARV dosage, with the attendant risks of side effects.
In addition the combination of a total of seven drugs puts a serious burden on the liver and increases the risk of drug toxicity.
Patients starting ARVs risk developing immune reconstitution inflammatory syndrome when their immune systems recover sufficiently to attempt to respond to all the opportunistic infections that have taken hold.
The theory was that curing a patient of TB would reduce the risk of the inflammation syndrome, which, in extreme cases, can kill.
But the Starting Antiretroviral Therapy in three Points in Tuberculosis Therapy (Sapit) trial clearly showed that, despite these concerns, starting antiretroviral therapy at the beginning of TB treatment in people with a CD4 count of less than 500 could cut mortality dramatically.
The trial was run by an international collaboration—the Centre for the Aids Programme of Research in South Africa (Caprisa), based at the University of KwaZulu-Natal.
Karim said that last year about 353 000 people were diagnosed with TB, 70% of whom also had HIV.
Experts in both diseases said that the results underscored the need to integrate treatment for HIV and TB and to allow trained nurses to start patients on ARVs at TB clinics.
Neil Martinson of the Perinatal HIV Research Unit said that, given the huge overlap between HIV and TB, it is crucial that treatment of the two diseases is integrated in facilities that will reduce the risk of patients getting fresh TB infections from one another. This is particularly important given the rise of drug-resistant TB.
Francois Venter, head of the Southern Africa HIV Clinicians’ Society, said: “Our TB programme needs to be seen as a key recruitment area for patients who are at high risk of death if they do not get antiretrovirals.
“Previously clinicians thought that antiretrovirals could be delayed in TB patients, depending on their CD4 count. This study suggests that a lot of people will die if we continue this policy.”
The Sapit trial had three arms. The one, which was halted early, treated patients once they had completed their TB treatment.
The other two started patients on ARVs while they were undergoing TB treatment, one giving patients the anti-HIV drugs when they had completed the first two “intensive phase” months of the TB course and the other starting patients on ARVs as soon as possible.
The latter two arms of the trial will continue until 2010, when the results should demonstrate whether it is best to wait at all before starting TB treatment in HIV-positive patients with CD4 counts of below 500.