Researchers recently reported the completion of a Phase-2 study for Imatinib for the treatment of AIDS-related Kaposi’s sarcoma and found the drug to be well-tolerated in patients. Imatinib is an inhibitor of stem cell factor receptors and platelet-derived growth factor receptors developed by Novartis and marketed under the name of Gleevec.
30 patients participated in the study and received 400 mg Imanitib daily for a maximun 12 months. Patients who showed stable disease received escalated doses up to 600 mg at a day for 3 months.
In the treatment duration ranging from 0.3 to 52.7 weeks, 9 patients (30%) completed a 52 week-treatment. 7 patients (23%) and 5 patients (17%) discontinued treatment due to disease progression and adverse events respectively.
6 patients (20%) demonstrated stable disease and 10 patients (33%) showed partial response in median response time of 21 weeks.
21 patients (70%) experienced adverse events of any grade, which include 11 cases of severe adverse events. 7 patients (23%) experienced progression of Kaposi’s sarcoma.
Mutations on stem cell factor and platelet-derived growth factor or any changes in the candidate cytokines were not observed. Notably, the antiretroviral therapy (a therapy applying antigen against retrovirus such as HIV) did not interfere with imatinib metabolism.
“This regimen may be useful as an alternative for patients who do not require cytotoxic chemotherapy or whose disease has progressed on conventional therapy,” the researchers wrote. “Exploration in classic Kaposi’s sarcoma may also be warranted, particularly because this is a disease of the elderly who may benefit from noncytotoxic therapies.”