Abbott HIV drug zaps viral loads in trial

DUBLIN, Ireland, Nov. 18 (UPI) -- Abbott said Friday that a seven-year study of its HIV drug Kaletra showed undetectable viral loads in patients.

The Phase 2 study -- which Abbott said is the longest ever for an HIV therapy -- showed that Kaletra, taken with other antiretroviral agents, maintained a viral level in most patients' blood of less than 50 copies per milliliter, as measured by HIV RNA.

The findings demonstrated that most patients taking a Kaletra-based regimen as initial therapy for HIV infection showed sustained anti-viral response, Abbott said.

Of the 19 patients who met criteria for resistance testing and had resistance testing results available through week 360, none demonstrated primary protease inhibitor resistance, the Abbott Park, Ill.-based firm said.

Specifically, data from the study of 100 treatment-naive patients taking Kaletra in combination with lamivudine and stavudine showed that 59 percent of patients had an undetectable viral load and 61 percent had HIV RNA less than 400 copies per milliliter, Abbott said.

The company said it used an "intent-to-treat" analysis, which categorizes any patient who does not complete the study as a treatment failure.

Of the 62 patients remaining on treatment at week 360, 98 percent had HIV RNA less than 400 copies per milliliter. The data were presented at the 9th European AIDS Conference in Dublin, Ireland.