The AIDS Clinical Trial Group (ACTG) Study Monitoring Committee has informed the ACTG and drugmaker Schering-Plough (SP) that five cases of cancer have occurred in an ongoing study of patients treated with the experimental HIV entry inhibitor vicriviroc.

The five cases involve four patients with lymphoma (malignant cancer of the lymph nodes) and one patient with adenocarcinoma (stomach cancer). The ACTG concluded that a causal association between vicriviroc and the lymphoma cases could not be established. Further, they said that because the drug demonstrated virologic activity and CD4 increases at the two highest doses, the trial will continue.

The ACTG-sponsored trial is a Phase II clinical study of vicriviroc among 118 US treatment-experienced patients. Patients enrolled in this trial have advanced HIV disease and low CD4 counts.

Patients and researchers in the trial have been informed of the 5 cancer cases.  The ACTG is taking additional measures to assure the safety of patients in the trial, according to a statement by SP.  These include introducing long term follow-up (3-5 years) and unblinding the patients in order that they and their physicians may make a more informed decision about their treatment options. 

The SP statement concludes, “Schering-Plough intends to continue to work closely with the ACTG as well as the US Food and Drug Administration (FDA) and other health authorities to fully determine the potential role of vicriviroc in HIV therapy.”

HIV and Hepatitis.com will continue to closely monitor developments in this situation and will post any significant updates as quickly as possible.

03/07/06

Source
Schering-Plough. SCHERING-PLOUGH PROVIDES UPDATE ON PHASE II STUDY OF VICRIVIROC. March 4, 2006.


Additional Vicriviroc Articles on HIVandHepatitis.com

Schering Revives Study of Experimental CCR5 Entry Inhibitor Vicriviroc in Treatment-naïve HIV Patients - 2/28/06

CCR5 Antagonist Vicriviroc Shows Potent Activity against HIV - 1/13//06

Schering-Plough Halts Phase II Study of CCR5 HIV Entry Inhibitor Vicriviroc - 10/28/05