NEW HIV STUDY SHOWS THAT LARGE NUMBERS OF WOMEN AND PEOPLE OF COLOR CAN BE SUCCESSFULLY ENROLLED IN U.S. HIV CLINICAL STUDIES

GRACE compares efficacy and safety of PREZISTA/ritonavir in treatment-experienced women vs. men at 48 weeks

GRACE findings were presented on July 20, 2009 at the 5th International AIDS Society Conference on HIV Pathogenesis, Treatment, and Prevention (IAS 2009) in Cape Town, South Africa.

In the United States, women are increasingly affected by HIV/AIDS, accounting for more than one quarter of all new HIV/AIDS diagnoses, with African American and Latina women representing 79 percent of women living with the disease.

Despite the increasing numbers of women with HIV, they have been under-represented in clinical treatment studies. In recent HIV studies of treatment-experienced patients, women accounted for less than 11 percent of the patients being studied, on average. GRACE was able to enroll 67 percent women and 84 percent people of color.

The GRACE (Gender, Race And Clinical Experience) study demonstrated that through 48 weeks of therapy, there were no statistically significant differences in virologic response rates between treatment-experienced women and men receiving the protease inhibitor PREZISTA (600 mg twice daily with 100 mg ritonavir), with a background regimen. In addition, there were no clinically relevant gender-based differences in adverse events.

"GRACE not only showed us that PREZISTA/r had similar efficacy and tolerability in treatment-experienced men and women, but it also taught us that through unique recruitment and retention strategies, a large number of women and people of color can enroll and stay in HIV clinical trials," said Kathleen Squires, MD, Director, Division of Infectious Diseases, Thomas Jefferson University and primary investigator in the GRACE study."

"GRACE has the potential to shape how future HIV studies should be conducted because it addressed head-on the social and economic barriers, such as lack of support, stigma, availability of child care and lack of transportation, which often have prevented women and people of color from participating in HIV clinical studies and remaining in care."

Tibotec Therapeutics Clinical Affairs, a division of Centocor Ortho Biotech Services, the sponsor of the GRACE study, assembled a group of physicians and advocates, some of whom are people living with HIV, to help design and advise on the GRACE study. The company is conducting additional research to determine from the participants' perspective which recruitment and retention strategies were most effective for them.

"GRACE sets a new standard for how future HIV studies should be conducted, as we now know that treatment-experienced women and people of color can and will successfully participate in clinical trials if the studies are designed and supported in the right way," said Dawn Averitt Bridge, Founder and Chair, The Well Project. "Tibotec truly partnered with the HIV community and we worked together to design novel strategies that overcame traditional barriers to enrollment of women and people of color, who are disproportionally affected by HIV/AIDS."

About the GRACE Study

GRACE is a multi-center, open-label phase 4 trial that compared gender differences in the efficacy, safety, and tolerability of PREZISTA tablets with 100 mg ritonavir in treatment-experienced, HIV-1-infected women and men. The trial enrolled 287 women and 142 men.

The main objective of this study was to compare the percentages of women and men who achieved virologic response, defined as a viral load of <50 copies/mL at week 48. Study participants received PREZISTA (600 mg) boosted with a low dose of ritonavir (100 mg) twice a day in combination with other antiretroviral drugs for 48 weeks.

Results from an intent-to-treat time-to-loss of virological response analysis (ITT-TLOVR) showed that 51 percent of treatment-experienced HIV-1 infected women reached an undetectable viral load (<50 copies/mL) at week 48, compared with 59 percent of men, (p=not significant).

When treatment discontinuations for reasons other than virologic failure were censored (non-VF censored-TLOVR), 73 percent of both women and men reached an undetectable viral load (p=not significant).

There were no clinically relevant differences in safety or tolerability between women and men.

In adult patients receiving a PREZISTA/r-containing regimen, the most common treatment-related adverse events (? 2 percent) reported of at least moderate to severe intensity (? Grade 2) were diarrhea (4.5 percent for women and 4.9 percent for men), nausea (5.2 percent for women and 2.8 percent for men), rash (2.1 percent for women and 2.8 percent for men), weight gain (1.7 percent for women 2.1 percent in men) and vomiting (1.4 percent in women and 2.1 percent in men).

Discontinuation rates due to adverse events were 7.7 percent for women and 4.2 percent for men, though no specific adverse event was listed as a reason for discontinuation in more than two people. Lost to follow-up was the most common reason for discontinuation.

"We are incredibly proud to have designed and conducted the GRACE study, and couldn't have done it without the collaboration of our physician and community advisors, as well as the women and men who participated in the study," said Glenn Mattes, President of Tibotec Therapeutics. "We hope that GRACE provides a new model for HIV research, so that enrollment in future clinical studies in the U.S. will reflect current trends in HIV/AIDS cases among women and communities of color."

Tibotec will also be presenting results from a GRACE sub-study at IAS 2009, examining recovery of functional immunity. Additional sub-studies from GRACE will follow.

PREZISTA Indication: Adults

PREZISTA, co-administered with ritonavir (PREZISTA/rtv), and with other antiretroviral agents, is indicated for the treatment of human immunodeficiency virus (HIV-1) infection.

This indication is based on analyses of plasma HIV RNA levels and CD4+ cell counts from 2 controlled Phase 3 trials of 48 weeks duration in antiretroviral treatment-naïve and treatment-experienced patients and 2 controlled Phase 2 trials of 96 weeks duration in clinically advanced, treatment-experienced adult patients.
In treatment-experienced adult patients, the following points should be considered when initiating therapy with PREZISTA/rtv: