537P - P2 study of ADXS11-001 Immunotherapy in patients with persistent/recurrent, surgically unresectable locoregional, or metastatic squamous cell anal...

Date 09 September 2017
Event ESMO 2017 Congress
Session Poster display session
Topics Drug Development
Anal Cancer
Cancer Immunology and Immunotherapy
Gastrointestinal Cancers
Presenter Cathy Eng
Citation Annals of Oncology (2017) 28 (suppl_5): v158-v208. 10.1093/annonc/mdx393
Authors C. Eng1, M. Fakih2, M. Amin3, V. Morris1, H.S. Hochster4, P.M. Boland5, H. Uronis6
  • 1Department Of Gastrointestinal (gi) Medical Oncology, MD Anderson Cancer Center, 77030 - Houston/US
  • 2Medical Oncology, City of Hope, 91010 - Duarte/US
  • 3Medical Oncology, Siteman Cancer Center, Washington University School of Medicine, 63110 - St. Louis/US
  • 4Yale University, Yale Cancer Center, New Haven/US
  • 5Medical Oncology, Roswell Park Cancer Institute, Buffalo/US
  • 6Medical Oncology, Duke Cancer Institute, 27710 - Durham/US

Abstract

Background

The number of new anal cancer (SCCA) cases in the US has been rising annually; 20% of patients (pts) will develop metastatic (met) disease, which presents an unmet medical need. A large population-based study showed 88% of SCCA were HPV+ and 73% had HPV-16 (Hoots et al IJC 2009). ADXS11-001 (ADXS) is an irreversibly attenuated Listeria monocytogenes immunotherapy that targets HPV-associated cancers. It is bioengineered to secrete an antigen-adjuvant protein fused to the E7 peptide of HPV-16. It allows the generation of tumor antigen specific cytotoxic T cells that infiltrate and destroy tumor cells. This is the 1st P2 trial to assess the efficacy/safety of ADXS in met SCCA.

Methods

This multicenter, open-label, 2-stage design trial (NCT02399813) includes pts ≥ 18 yrs with histologically confirmed, measurable SCCA and previous ≥ 1 line of therapy for advanced disease. Pts received IV ADXS monotherapy (1x109 colony forming units) every 3 weeks for ≤ 2 years or until a discontinuation criterion was met. Tumor assessments (RECIST 1.1) were every 9 wks. Interim analysis was planned on enrollment of 31 evaluable pts (≥ 1 post-baseline scan). An objective response rate (ORR) ≥ 10% or a 6-month progression free survival (PFS) ≥ 20% with tolerable safety would allow proceeding to Stage 2.

Results

Preliminary Stage 1 results are reported with data from 29 of the planned 31 evaluable pts. Median age 60 yrs, range 43-77; 27 F/2 M; median follow-up time 191 days. One pt (3.5%) had a durable partial response lasting > 6 months (after progression on prior anti-PD-1 therapy) and 7 pts had stable disease (24%). Disease control rate was 28%. The current KM 6-month PFS estimate is 22%. Common (≥ 30%) treatment related AEs (TRAEs) were grade 1-2 chills/rigors, fever, hypotension and vomiting. Grade 3 TRAEs of cytokine related syndrome (n = 1; SAE), infusion related reactions (n = 2; 1 SAE) and hypotension (n = 2; 1 SAE) were reported.

Conclusions

ADXS monotherapy showed promising activity and met the predefined 6-month PFS rate. Treatment was well-tolerated with mostly grade 1-2 infusion related AEs that resolved successfully with standard care. Further investigation is ongoing in this population.

Clinical trial identification

NCT02399813

Legal entity responsible for the study

Advaxis, Inc

Funding

Advaxis, Inc

Disclosure

C. Eng: Consulting agreement with Advaxis. All other authors have declared no conflicts of interest.