Emergent BioSolutions Inc. has initiated a phase II study (protocol 16201) of TRU-016 in combination with bendamustine for patients with relapsed chronic lymphocytic leukaemia (CLL). This initiation of clinical trial triggers a $6 million milestone payment to Emergent. TRU-016 is a humanized anti-CD37 mono-specific protein therapeutic in development for the treatment of B-cell malignancies.

“Preclinical studies have demonstrated increased anti-tumour activity for the combination of bendamustine and TRU-016 beyond the results achieved when either drug was administered alone,” said Scott C Stromatt, MD, senior vice president and chief medical officer, Emergent BioSolutions Inc. “The safety data from the phase Ib portion of the combination trial of TRU-016 with bendamustine in relapsed CLL was recently reviewed by an independent Data Monitoring Committee, and they authorized advancement into phase II.”

The open-label, multi-centre, active-controlled study is enrolling bendamustine-naïve patients with a confirmed diagnosis of relapsed CLL and who have failed up to three previous treatments. The phase Ib portion of the study evaluated 12 patients with relapsed CLL to determine a safe and tolerable dose of TRU-016 in combination with bendamustine. The primary endpoint for the phase Ib portion was the incidence of dose-limiting toxicities.

The phase II portion of the study will evaluate the safety and efficacy of TRU-016 in combination with bendamustine compared with bendamustine alone in a total of approximately 100 randomized patients. TRU-016 will be dosed over six 28-day cycles. The primary endpoint for the phase II study is an overall response rate as defined by 2008 International Workshop on Chronic Lymphocytic Leukaemia (IWCLL) criteria. Secondary endpoints include complete and partial response rates as defined by the 1996 National Cancer Institute (NCI) criteria, progression-free survival, duration of response, and improvement in quality of life and disease symptoms.

Pharmacokinetics and pharmacodynamics of TRU-016 will be studied in both phases of the study.

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