Integrase Inhibitors Best for HIV Patients With Cancer
Analysis of RTOG 0617 trial evaluates the impact of high-dose radiation therapy
DENVER — For HIV-infected patients with cancer undergoing chemotherapy, the integrase strand-transfer inhibitor raltegravir is the best choice for viral suppression, according to a new study. The efficacy of raltegravir is similar to that of non-nucleoside reverse-transcriptase inhibitors, but the rate of adverse events is lower. Because HIV patients are living longer, cancer treatment and management is becoming a clinical issue. About 33% of deaths in HIV patients are now attributable to cancer, according to Harrys Torres, MD, assistant professor of infectious diseases at the University of Texas M.D. Anderson Cancer Center in Houston. Antiretroviral drugs and cancer medications have various interactions. Although these have been studied, there are no data on the clinical efficacy of different antiviral therapies in cancer patients. "In the clinic, we don't know which one to use," Dr. Torres told Medscape Medical News. His team conducted a retrospective analysis of adults with HIV and any type of cancer seen at M.D. Anderson. Dr. Torres presented the research here at the 53rd Interscience Conference on Antimicrobial Agents and Chemotherapy.
All 154 study participants had their therapy initiated or monitored by an infectious disease specialist at M.D. Anderson, and made at least 2 visits there in a 6-month period. The majority of the patients were male (81%) and white (52%). Treatment consisted of optimized background therapy with nucleoside reverse-transcriptase inhibitors plus protease inhibitors, non-nucleoside inhibitors, integrase inhibitors, or some combination thereof. The researchers defined efficacy as the absence of virologic failure (HIV RNA viral load >200 copies/mL for more than 6 months) or virologic rebound (HIV RNA viral load >200 copies/mL after virologic suppression) during antiretroviral therapy. Of the 60% of patients with hematologic malignancies, most (74%) presented with non-Hodgkin's lymphoma. At 6 months, protease inhibitors were less effective than integrase (P = .005) and non-nucleoside inhibitors (P = .001). Integrase inhibitors had the fewest adverse effects (P = .001).
Table: Outcomes With Agents Added to Optimized Background Therapy
|Treatment||Efficacy at 6 Months, %||Adverse Effects, %|
|Integrase strand-transfer inhibitors (n = 30)||96||3|
|Protease inhibitors (n = 57)||65||35|
|Non-nucleoside reverse transcriptase inhibitors (n = 50)||97||14|
|Combination (n = 17)||78||6|
"The only integrase inhibitor we studied was raltegravir, because it was the only one available. We don't know if the results will be the same for other integrase inhibitors, but they seem to be the way to go with patients who have hematologic malignancies and are receiving concomitant chemotherapy. Hematologic cancers are the most difficult to treat because they require highly immunosuppressive chemotherapy in preparation for stem cell transplantation," Dr. Torres explained.
These results should help inform clinical decisions. "It's very important. In our center, the number of cancer patients is higher than in past years; we see colon cancers, lymphomas, and anal cancers. It's very difficult to combine chemotherapy with antiretroviral therapy because of the drug interactions," said Otto Sussmann, MD, infectious diseases specialist at Asistencia Cientifica de Alta Complejidad in Bogotá, Columbia, who attended the session.
Dr. Sussmann said he has immediate plans to incorporate the study results into his center's practice. "Next week, in the meeting with our group, I will comment on this work and we will decide on better antiretroviral therapy for our patients," he told Medscape Medical News.
Source: MedScape News: http://www.medscape.com/viewarticle/811489