According to an aidsmap report, the first study in the ENCORE (Evaluation of Novel Concepts in Optimization of Antiretroviral Efficacy) research program will be a 700-person clinical trial comparing two doses of Sustiva (efavirenz)—the standard dose (600 mg once daily) and a lower dose (400 mg once daily). Reducing the dose by one third would likely translate into significant cost savings—a key issue in resource-poor countries—and might cause fewer side effects, including central nervous system problems.

ENCORE, led by Sydney-based researchers Sean Emery, MD, and David Cooper, MD, will begin recruiting patients for its first study during the second half of 2009, with sites in Europe, Asia, Australia, Latin America and North America. Results from the 96-week efavirenz dose comparison are expected by 2013.

The research program will also explore lower doses of Epivir (lamivudine) and Kaletra (lopinavir/ritonavir). Other ARVs suggested to be effective at lower doses include Retrovir (zidovudine), Reyataz (atazanavir) and Zerit (stavudine).