Pilot Trial of SP-2577 Plus Pembrolizumab in Select Gynecologic Cancers

Pilot Feasibility and Efficacy Trial of a Novel Reversible LSD1 Inhibitor SP-2577 (Seclidemstat) Plus Pembrolizumab in Select SWI/SNF-mutant Gynecologic Cancers

Open-label study of SF-2577 plus pembrolizumab in advanced, recurrent small cell ovarian cancer as well as select additional ovarian and endometrial cancers within the SWI/SNF pathway.

Study Overview

• Status: Withdrawn
• Conditions: Ovarian Endometrioid Adenocarcinoma; Endometrial Cancer; SCCOHT; Ovarian Clear Cell Tumor
• Intervention / Treatment: Drug: SP-2577; Drug: Pembrolizumab

Detailed Description

This study is an open-label, non-randomized dose escalation and expansion study of the LSD inhibitor SP-2577 in combination with the anti PD- 1 antibody pembrolizumab in patients with advanced, recurrent small cell ovarian cancer of the hypercalcemic type (SCCOHT) as well as select additional ovarian and endometrial cancers with mutations in the genes within the SWI/SNF pathway (Ovarian Clear Cell Cancers (OCCC), Endometrioid Ovarian Cancers (EOC) and Endometrioid Endometrial Cancers (EEC).

• Study Type: Interventional
• Phase: Phase 1

Contacts and Locations

Study Locations

• United States
  • Arizona
    • Scottsdale, Arizona, United States, 85258
      • HonorHealth Research Institute

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Female participants who are at least 18 years of age on the day of signing informed consent with histologically confirmed diagnosis of small cell carcinoma of the ovary of hypercalcemic type (SCCOHT), ovarian clear cell carcinoma (OCCC), endometrioid ovarian carcinoma (EOC) or endometrioid endometrial carcinoma (EEC) with confirmed mutations in one of the SWI/SNF genes (SMARCA4, ARID1A) will be enrolled in this study.
• Patients must have received at least one prior regimen in the recurrent or advanced setting and must not be a candidate for other potentially curative treatment options.
• Not pregnant, breastfeeding and agrees to use contraceptive methods if child-bearing
• Provides written informed consent
• Have measurable disease based on RECIST 1.1. Lesions situated in a previously irradiated area are considered measurable if progression has been demonstrated in such lesions.
• Have provided archival tumor tissue sample or a newly obtained core or excisional biopsy of a tumor lesion not irradiated.
• ECOG of 0 to 1
• Adequate organ function

Exclusion Criteria:

• A WOCBP who has a positive urine pregnancy test within 72 hours prior to allocation.
• Prior therapy with an anti-PD-1, anti-PD-L1, or anti-PD-L2 agent is allowed as long as patient did not have a serious (≥ Grade 3) immune related AE requiring treatment discontinuation or treatment with systemic steroids.
• Has received prior therapy with LSD1 targeted agents including monoamine oxidases for cancer therapy.
• Has received prior systemic anti-cancer therapy including investigational agents within 4 weeks or 5 half-lives whichever is shorter prior to the first dose of study treatment.
• Has received prior radiotherapy within 2 weeks of start of study treatment.
• Has received a live vaccine within 30 days prior to the first dose of study drug.
• Is currently participating in or has participated in a study of an investigational agent or has used an investigational device within 4 weeks prior to the first dose of study treatment.
• Has a diagnosis of immunodeficiency or is receiving chronic systemic steroid therapy (in dosing exceeding 10 mg daily of prednisone equivalent) or any other form of immunosuppressive therapy within 7 days prior to the first dose of study drug.
• Has a known additional malignancy that is progressing or has required active treatment within the past 3 years.
• Has known active CNS metastases and/or carcinomatous meningitis.
• Has severe hypersensitivity (≥Grade 3) to pembrolizumab and/or any of its excipients.
• Has active autoimmune disease that has required systemic treatment in the past 2 years (i.e. with use of disease modifying agents, corticosteroids or immunosuppressive drugs).
• Has a history of (non-infectious) pneumonitis that required steroids or has current pneumonitis.
• Has an active infection requiring systemic therapy.
• Has a known history of HIV, Hepatitis B, or known active Hepatitis C
• Has a known history of active TB
• Has clinically significant, uncontrolled heart disease and/or cardiac repolarization abnormality
• Is currently receiving any of the following substances and cannot be discontinued 14 days, or 5 half-lives for CYP inhibitors (whichever is shorter) prior to Cycle 1 Day 1
• Has a history or current evidence of any condition, therapy, or laboratory abnormality that might confound the results of the study, interfere with the subject's participation for the full duration of the study, or is not in the best interest of the subject to participate, in the opinion of the treating investigator.
• Has known psychiatric or substance abuse disorders that would interfere with cooperation with the requirements of the trial.
• Is pregnant or breastfeeding, or expecting to conceive within the projected duration of the study, starting with the screening visit through 120 days after the last dose of trial treatment.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: SP-2577 Plus Pembrolizumab	Drug: SP-2577; Daily oral doses; Drug: Pembrolizumab; 200mg Q3W by IV infusion

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incident of AEs	Incidence of Adverse Events (AEs) as measured by NCI CTCAE version 5.0	First dose to 90 days after last dose
Incident of DLTs	Incidence of dose-limiting toxicities (DLTs) during the dose escalation phase	First dose to 90 days after last dose
Overall Response Rate	Percentage of participants with a best overall response of Complete Response (CR) or Partial Response (PR), as determined by Investigator according to Response Evaluation in Solid Tumors (RECIST) v 1.1	Study enrollment until participant discontinuation, occurrence of PD or death (approximately 6 months to 3 years)
Disease Control Rate	Percentage of participants with Disease Control (complete response, partial response, or stable disease) as determined by RECIST v1.1	Study enrollment until PD or loss of clinical benefit (approximately 6 months to 3 years)
Duration of Response	Duration of Response as determined by the Investigator according to RECIST v1.1	Date of first occurrence of objective response to first documentation of PD (approximately 6 months to 3 years)
Duration of Stable Disease	Duration of Stable Disease as determined by the investigator according to RECIST v 1.1	Date of first occurrence of stable disease to first documentation of PD (approximately 6 months to 3 years)
Progression Free Survival	Progression Free Survival (PFS) as determined by the Investigator according to RECIST v1.1	Start of treatment to first occurrence of PD or death (approximately 6 months to 3 years)
Overall Survival	Overall Survival (OS) as determined by the Investigator according to RECIST v1.1	Start of treatment to death (approximately 2 to 3 years)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Plasma Concentration of SP-2577	Plasma concentration of seclidemstat (SP-2577)	2 months
ctDNA in blood and other body fluids	Proportion of circulating tumor DNA ( ctDNA) in peripheral blood and other body fluids e.g. ascitic fluid	6 months to 2 years
Target Inhibition in Tumor Biopsies	Percentage of target inhibition by seclidemstat and pembrolizumab in tumor tissue biopsy specimens	6 months to 2 years

Collaborators and Investigators

• Sponsor: HonorHealth Research Institute
• Collaborators: Merck Sharp & Dohme LLC; Salarius Pharmaceuticals, LLC

Study record dates

Study Major Dates

• Study Start (Anticipated): December 31, 2021
• Primary Completion (Anticipated): December 31, 2023
• Study Completion (Anticipated): June 30, 2024

Study Registration Dates

• First Submitted: September 24, 2020
• First Submitted That Met QC Criteria: October 26, 2020
• First Posted (Actual): November 2, 2020

Study Record Updates

• Last Update Posted (Actual): March 2, 2022
• Last Update Submitted That Met QC Criteria: February 11, 2022
• Last Verified: February 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neoplasms by Histologic Type; Neoplasms; Urogenital Neoplasms; Neoplasms by Site; Adenocarcinoma; Carcinoma; Neoplasms, Glandular and Epithelial; Uterine Neoplasms; Genital Neoplasms, Female; Uterine Diseases; Endocrine System Diseases; Ovarian Diseases; Adnexal Diseases; Gonadal Disorders; Ovarian Neoplasms; Endometrial Neoplasms; Carcinoma, Endometrioid; Antineoplastic Agents; Antineoplastic Agents, Immunological; Pembrolizumab
• Other Study ID Numbers: HRI-SP-2577-001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No