Research Centers


Cost Effectiveness of Preventing AIDS Complications (CEPAC)

Cost Effectiveness of Preventing AIDS Complications (CEPAC) is an HIV clinical modeling team that compares the effectiveness of different HIV treatment strategies, in collaboration with investigators around the world.


Since 1994, the Cost-Effectiveness of Preventing AIDS Complications (CEPAC) team, led by Drs. Kenneth Freedberg and Rochelle Walensky at Massachusetts General Hospital, has used a Monte Carlo simulation model to evaluate the cost-effectiveness of national and multinational strategies for combating HIV/AIDS. The model, first developed in response to the outbreak of the HIV/AIDS epidemic in the United States, has grown over time in both scope and application to provide comprehensive analyses for prospective treatment strategies of HIV/AIDS and AIDS-related complications, including tuberculosis and other infections.

The CEPAC team collaborates with research teams in Botswana, Brazil, Côte d’Ivoire, France, India, Mozambique, South Africa, and Zimbabwe, as well as investigators from Brigham and Women’s Hospital, the Harvard School of Public Health, Weill Cornell Medical College, and Yale University. Research from the CEPAC team has been published in several leading medical journals, including the Journal of the American Medical Association, New England Journal of Medicine, and AIDS. For more information, visit our website.

Group Members


  • Kenneth A. Freedberg, MD, MSc
  • Rochelle P. Walensky, MD, MPH

For a full list of group members with research interests including fellows, software engineers, biostatisticians, project specialists, project coordinators, and research assistants, please visit our website.

Research Projects

At the center of CEPAC research is the CEPAC model. The CEPAC model simulates a large cohort of patients and follows each patient on a monthly basis until death. CEPAC uses published data on the natural history of HIV and opportunistic infections, as well as the efficacy and cost of prophylaxis and treatment along with other epidemiological parameters to simulate the overall impact of HIV on a specific population.

CEPAC researchers simulate prospective treatment strategies onto the cohort under varying epidemiological conditions and use the outputs to project a strategy’s efficacy and cost-effectiveness.

CEPAC (Cost Effectiveness of Preventing AIDS Complications)

50 Staniford Street
9th floor
Boston, MA 02114

Phone: 617-724-8445

Public Transportation Access: yes
Disabled Access: yes