DPX-Survivac and Checkpoint Inhibitor in DLBCL

Official Title

Phase 2 Study of an Immunotherapeutic Vaccine, DPX-Survivac With Low Dose Cyclophosphamide Administered With Pembrolizumab in Patients With Persistent or Recurrent/Refractory Diffuse Large B-Cell Lymphoma (DLBCL)

Summary:

This is a Phase 2 non-randomized, open label, uncontrolled, efficacy and safety study. Study participants will receive two priming doses of 0.5mL of DPX-Survivac 21 days apart and up to six 0.1ml maintenance injections every two months with low dose metronomic oral cyclophosphamide (50 mg BID) for one year or until disease progression, whichever occurs first. Pembrolizumab 200 mg will be administered every 3 weeks for up to one year or until disease progression, whichever occurs first.

Trial Description

Primary Outcome:

• To document the objective response rate using modified Cheson criteria to treatment with DPX-Survivac and low dose cyclophosphamide administered together with Pembrolizumab in participants with recurrent, survivin-expressing B cell lymphomas

Secondary Outcome:

• To document changes in tumour volume using waterfall analyses
• To document the toxicity profile
• To document duration of response using modified Cheson criteria.
• To document time to next treatment

This is a Phase 2, non-randomized, open-label, uncontrolled, efficacy and safety trial. Participants will receive 2 priming injections (0.5ml) of DPX-Survivac 3 weeks apart on Study Days 7 and 28. In addition, up to 6 maintenance injections (0.1ml) over the course of the study occurring on Study Days 84, 140, 196, 252, 308, and 364. All injections will be given under the skin of the upper thigh. Participants will receive metronomic oral cyclophosphamide (50mg BID; 7 days on / 7 days off) for study period. Pembrolizumab 200mg will be administered intravenously every 3 weeks, commencing on study day 7, to a total of 18 infusions. If a participant is removed from the trial prior to the completion of at least 4 doses of Pembrolizumab and 3 injections of DPX-Survivac, that particiapnt may be replaced to determine the efficacy of treatment in a minimum of 16 participants. DPX-Survivac injection sites will be evaluated throughout the study and if evidence of significant reaction, an Injection site reaction biopsy will be sought. During the course of the study, blood will be drawn to evaluate immune cells and the effect that DPX Survivac will have on the participants immune system. During all treatment cycles a physical exam and questions about the participants general health will be performed. Participants will undergo "re-staging" to assess the status of their disease at approximately study day 70 (if there is evidence of Grade 2 or greater injection site reaction or ulceration evident on study day 49) or routinely at approximately study day 91, and again at end of study or study withdrawal for all participants. A follow-up tumour biopsy will be requested between study day 77-83 for participants with any grade 2 or greater Injection site reaction or ulceration on SD49 or between SD98 and SD104 if no evidence of injection site reaction or ulceration. Upon completion of study, participants will be monitored every 2 months for 1 year.

View this trial on ClinicalTrials.gov