One new scientific finding released today at the HIV/AIDS Implementers’ Meeting: a large-scale study found CD4 tests determined correctly whether a patient was not responding to treatment only in 37 percent of the cases.
The study, presented by Phyllis Kanki, the principal investigator for Harvard’s PEPFAR programs in three African countries, found that viral load testing was the only sure way to detect failure in treatment regimens.
In past years, PEPFAR headquarters has argued against viral load testing because of cost and the inability of many sites to do the tests. Many US government-supported sites now rely on CD4 tests to detect failure. In Harvard’s program, the testing cost about $50 per patient in the first year, and $30 in following years.
Kanki’s study of 11,497 patients found, however, that relying on CD4 tests would have cost her program roughly $900,000 a year because of the high number of wrong diagnoses. The cost would be high because each patient believed to have failed treatment needs to go on more expensive second-line therapy.
“My conclusion is if you have ability to do viral load testing, you should do it,’’ Kanki said after her presentation. “But we should also be advocating for cheaper tests for viral loading. Five years ago, some people said we couldn’t treat people in Africa because the drugs were too expensive. For five years, the prices have gone down. If you now say you can’t do viral load testing in Africa because of cost, you will never have groups that will develop these tests at a more affordable price.’’