Initial phase II results of SGN-30 (anti-CD30 monoclonal antibody) in patients with refractory or recurrent systemic anaplastic large cell lymphoma (ALCL)

Abstract

6601 Background: SGN-30 is a chimeric monoclonal antibody (mAb) directed against the CD30 antigen expressed on hematologic malignancies. SGN-30 was well tolerated in phase I and objective responses were seen. Methods: Refractory or recurrent CD30 positive ALCL patients, ECOG performance status 0–2, are treated in a multicenter, single arm phase II study. SGN-30 at 6 mg/kg is administered by short IV infusion weekly for 6 consecutive doses. A two stage statistical design provides a 90% power to detect an objective tumor response rate of at least 30%. Results: Patient Characteristics: 8 patients (3 male, 5 female) with median age 59 years have been enrolled. Median number of prior therapies is 2.5 (range 1–5). 88% of patients have received prior CHOP. Efficacy: 6 patients are evaluable for efficacy with 1 CR, 1 PR, 1 SD and 3 PD. The patient with a CR had a chest wall mass measuring 5.1 x 2.0 cm which disappeared completely after 6 doses of SGN-30. The duration of the CR is 49+ days. The patient with a PR had extensive cutaneous and nodal disease and constitutional symptoms. After treatment there was resolution of all skin lesions, reduction in lymphadenopathy and improvement in the constitutional symptoms. Assessment of duration of response was not possible as the protocol (subsequently amended) did not permit further therapy and the patient was switched to chemotherapy after 28 days. Tolerability: The most common adverse events included cough, diarrhea, fatigue, hoarseness, muscle weakness, rigors and vomiting. Each occurred in at least 2 patients. Only one grade 3/4 adverse event of catheter related infection was thought possibly related to SGN-30. Conclusions: The drug is well tolerated and shows signs of antitumor activity. Recruitment into the study continues. Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Seattle Genetics Seattle Genetics