Abstract 759P
Background
Here we report the first intermediate analysis of a randomized prospective multi-center clinical study aimed to evaluate safety and efficacy of p62/SQTM1-encoding plasmid applied as an adjuvant to chemotherapy in patients with advanced platinum-resistant ovarian cancer. Previously we reported that the p62-plasmid reduces chronic inflammation, changes the tumor microenvironment, and increases the number of tumor-infiltrating lymphocytes. In a phase I/IIa study in patients with refractory solid tumors, the plasmid demonstrated high degree of safety and preliminary indications of efficacy.
Methods
We analyzed the treatment interim result in 21 patients with advanced platinum-resistant ovarian cancer. Chemotherapy (gemcitabine 1000 mg/m2 days 1,8 every 3 weeks) was administered in the control arm patients (n=11). In the treatment arm, patients (n=10) received the chemotherapy plus p62-plasmid (2.5 mg weekly).
Results
To date, the median follow-up was 5.1 months. The median progression-free survival (PFS) was 2.4 and 5.7 months in the control and treatment arms, respectively (p=0.08). Two deaths due to disease progression in the control arm were observed and no deaths in the treatment arm. The response was assessed in 18 patients according to the RECIST 1.1 criteria (8 in the treatment arm and 10 in the control arm). No complete responses were observed in either group. The objective response rate was higher in the p62 treatment group: partial response (PR) 0% and 37.5%, stable disease (SD) 50% and 50%, disease progression 50.0% and 12.5%, minimal clinical repose (PR and SD) was observed as 50% and 87.5% in control and treatment arms, respectively (p=0,001). No Grade 3-4 toxicities were observed. All adverse effects were managed by conventional medications.
Conclusions
The interim results of our study showed that adding p62/SQSTM1-encoding plasmid to standard gemcitabine chemotherapy for advanced platinum-resistant ovarian cancer appears to be safe, well tolerated and effective. The study is ongoing.
Clinical trial identification
Editorial acknowledgement
The authors would like to thank Dr. Robert Devlin and Mr. Aaron Shneider for editorial assistance.
Legal entity responsible for the study
N.N. Alexandrov National Cancer Center of Belarus.
Funding
Has not received any funding.
Disclosure
Y. Baranau: Financial Interests, Personal, Invited Speaker: Roche; Financial Interests, Personal, Invited Speaker: Novartis; Financial Interests, Personal, Invited Speaker: Takeda; Financial Interests, Personal, Other, Travel Grant: Pfizer; Financial Interests, Personal, Advisory Board: Takeda; Financial Interests, Personal, Advisory Board: Novartis; Financial Interests, Institutional, Invited Speaker: Celltrion; Financial Interests, Institutional, Invited Speaker: BeiGene; Financial Interests, Institutional, Invited Speaker: Roche; Financial Interests, Institutional, Invited Speaker: Dr. Reddy's; Financial Interests, Institutional, Invited Speaker: Janssen. V. Gabai: Financial Interests, Personal, Full or part-time Employment: CureLab Oncology, Inc. A. Shneider: Financial Interests, Personal, Full or part-time Employment: CureLab Oncology, Inc. All other authors have declared no conflicts of interest.