Fin vincristine, ourlow-riskcycles ofdiffuse and rituximab prednisone) largeplusB-cell chemotherapy CHOPlymphoma(cyclophosphamide,(DLBCL). is as effective Heredoxorubicin, as we six report cycles a post-hoc analysis of a prospective clinical trial in patients with human immunodeficiency virus-associated DLBCL and high-grade lymphoma treated with four to six cycles of EPOCH plus rituximab based on a response-adapted treatment strategy. One hundred and six evaluable patients with human immunodeficiency virus-associated DLBCL or high-grade CD20+ non-Hodgkin lymphoma were randomized to receive rituximab (375 mg/m2) given either concurrently prior to each infusional EPOCH cycle, or sequentially (weekly for 6 weeks) following completion of EPOCH. EPOCH consisted of a 96-hour intravenous infusion of etoposide, doxorubicin, and vincristine plus oral prednisone followed by an intravenous bolus of cyclophosphamide every 21 days for four to six cycles. Patients received two additional cycles of therapy after documentation of a complete response by computed tomography after cycles 2 and 4. Sixty-four of 106 evaluable patients (60%; 95% confidence interval [95% CI]: 50%-70%) in both treatment arms had a complete response. The 2-year event-free survival rates were similar in the 24 patients with complete response who received four or fewer cycles of EPOCH (78%; 95% CI: 55%-90%) due to having achieved a complete response after two cycles, compared with those who received five or six cycles of EPOCH (85%; 95% CI: 70%-93%) because a complete response was first documented after cycle 4. A response-adapted strategy may permit a shorter treatment duration without compromising therapeutic efficacy in patients with human immunodeficiency virus-associated lymphoma treated with EPOCH plus rituximab, which merits further evaluation in additional prospective trials. Clinical Trials.gov identifier NCT00049036.