Drug & Device Development

AMD11070 shows action against X4-tropic HIV

Last Updated: 2009-04-09 19:04:13 -0400 (Reuters Health)

NEW YORK (Reuters Health) - AMD11070, an orally bioavailable inhibitor of CXCR4-tropic HIV is effective in reducing the X4 virus population in patients, researchers report in the March 15th issue of Clinical Infectious Diseases. Nevertheless, the study has been halted because of potential toxicity observed in animal studies.

Dr. Graeme Moyle of Chelsea Westminster Hospital, London and colleagues, who note that X4-tropic viruses are found with increasing frequency as CD4 cell counts decrease, used the agent in 10 patients. All had an X4 virus population of 2000 or more relative luminescence units (rlu).

Eight of the patients were given 200 mg of AMD11070 twice daily for 10 days. By error, the remaining 2 subjects received only 100 mg twice daily.

Four of the 9 evaluable patients achieved a reduction in X4 virus population of at least 1 log10 rlu. The median change in this population at the end of treatment was 0.22 log10 rlu. The largest reduction was 1.9 log10 rlu in one of the patients who received the 100 mg dose.

The X4 virus population increased in all the responding patients after the end of treatment and by day 30 was close to baseline levels.

The drug was well tolerated and there was no evidence of liver toxicity. However, clinical development is currently halted because of histologic changes in the liver observed in long-term animal studies, the researchers add. Doses employed were in the range of those tested clinically.

Clin Infect Dis 2009;48:798-805.