Pfizer will invest $25 million in Monogram through a 3-percent senior secured convertible note, payable in May 2010. The investment is expected to close this month, Monogram said.
In addition, Pfizer will continue to use Monogram's co-receptor tropism assay in clinical trials for its investigational CCR5 inhibitor drug candidate, maraviroc.
Pfizer has already used the assay to select patients for enrollment in late-stage clinical studies for the candidate, and the new agreement "expands this clinical trial collaboration and provides for global availability of Monogram's assay in a multi-year collaboration," the companies said.
"Monogram will take the lead in commercialization of the Co-Receptor Tropism Assay in the
Tropism information is used to identify patients who are most likely to respond to CCR5 antagonists, which are designed to block viral cell entry through the CCR5 co-receptor.
According to Monogram, 80 percent to 85 percent of people newly diagnosed with HIV and previously untreated with HIV therapy have dominant CCR5-tropic virus. This drops to 50-60 percent in patients who have been treated with anti-retroviral medicines.
Monogram, formerly called ViroLogic, began supplying Pfizer with HIV resistance testing technology and services in 2002, at which time Pfizer made an equity investment in the firm for an undisclosed amount.
The new collaboration agreement runs through Dec. 31, 2009, and may be renewed by Pfizer for five successive one-year terms.