Response rates up to 50% have been observed in patients with relapsed CD20-positive non-Hodgkin’s lymphoma after treatment with the chimeric monoclonal anti-CD20 antibody rituximab (Rituxan). The malignant cell population in
Response rates up to 50% have been observed in patients withrelapsed CD20-positive non-Hodgkin’s lymphoma after treatment with thechimeric monoclonal anti-CD20 antibody rituximab (Rituxan). The malignant cellpopulation in lymphocyte-predominant Hodgkin’s disease (LPHD) also expressesthe CD20 antigen in high density, while only 20% of all Hodgkin-Reed-Sternbergcells in classical Hodgkin’s disease (HD) are CD20 positive.
This phase II study investigates the safety and efficacy of 4 ×375 mg/m2 rituximab in patients with relapsed LPHD or CD20-positive classicalHD. Eligibility criteria included expression of the CD20 antigen on more than30% of all malignant cells; histologic slides had to be reviewed by a referencepanel.
Six patients (five males, one female) have been treated so far(as of June 2000). Median age was 37 years (range: 26 to 52 years); median timesince first diagnosis was 3 years (range: 1.7 to 5.9 years). All patients had atleast one prior chemotherapy: all five patients with LPHD were in first relapse,while the HD patient had been treated with two previous therapeutic regimens,including autologous peripheral stem cell transplantation. With 375 mg/m2rituximab weekly × 4 toxicity was moderate and transient. Side effectscomprised chills, fever, and hypotension. At 5 months of median follow-up(range: 1 to 9 months), response rates were 100% (4 complete remissions, 1partial remission) for patients with relapsed LPHD. The patient with therelapsed classical HD is in complete remission 10 months after completion oftherapy.
CONCLUSION: Administration of rituximab to patients with LPHD orCD20-positive classical HD is safe and feasible. These preliminary data suggesthigh efficacy with response rates up to 100%. Longer follow-up is necessary.Because the number of patients with LPHD and CD20-positive classical HD issmall, international cooperation has been started.