Trial of Pembrolizumab Following Weekly Paclitaxel for Platinum-resistant Ovarian, Fallopian Tube or Peritoneal Cancer (PROMPT)

Phase II Trial of Maintenance Pembrolizumab Following Weekly Paclitaxel for Platinum-resistant Ovarian, Fallopian Tube or Peritoneal Cancer

The overall aim of the study is to demonstrate a clinically meaningful extension of progression free survival using maintenance pembrolizumab. The aim of the translational research is to study the immune microenvironment before and during pembrolizumab therapy.

Study Overview

• Status: Completed
• Conditions: Ovarian Cancer; Fallopian Tube Cancer; Peritoneal Cancer
• Intervention / Treatment: Drug: Pembrolizumab

Detailed Description

This study aimed to investigate the effect of maintenance pembrolizumab in patients who underwent treatment with weekly paclitaxel for platinum-resistant recurrent ovarian cancer and either responded or progressed after a minimum of 4 cycles of treatment.

Participants were enrolled to receive 3 weekly pembrolizumab until progression. This was a non-randomised phase II study, and the population may be different from those who received paclitaxel and bevacizumab.

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Phase 2

Contacts and Locations

Study Locations

• United Kingdom
  • London, United Kingdom
    • UCLH
  • London, United Kingdom
    • Barts
  • London, United Kingdom
    • Imperial
  • Oxford, United Kingdom
    • Churchill Hospital

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Patients must have a diagnosis of high grade recurrent ovarian/fallopian tube or primary non-mucinous peritoneal cancer
2. Be willing and able to provide written informed consent for the trial, indicating that the patient has been informed of and understands the experimental nature of the study, possible risks and benefits, trial procedures, and alternative options
3. Be >=18 years of age on day of signing informed consent
4. Patients should be treated with a minimum of 4 cycles of weekly paclitaxel for recurrent disease. [Non-platinum-based therapy given for CT/MR documented recurrence where further platinum therapy considered unsuitable]
5. Patients can have had up to 3 prior lines of platinum-based chemotherapy for ovarian cancer before starting weekly paclitaxel
6. Patients must have achieved at least stable disease or response following a minimum of four cycles of weekly paclitaxel (measured by CT/MR)
7. Trial treatment with pembrolizumab must start within 8 weeks after last paclitaxel dose
8. Availability of archival tissue
9. Fresh tumour biopsy should be taken at baseline if this is judged by radiological assessment to be technically feasible. If a biopsy is taken at baseline, then a second biopsy should be taken, if feasible before the start of cycle 4
10. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1
11. Willing and able to comply with the protocol for the duration of the study, including the treatment plan, investigations required and follow up visits
12. Demonstrate adequate organ function as defined in the protocol, all screening labs should be performed within 10 days of treatment initiation.
13. Patients of childbearing potential should have a negative urine or serum pregnancy test. If the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be required
14. Patients of childbearing potential must be willing to use an adequate method of contraception as outlined in protocol from the start of treatment through to 4 months after the last dose of study medication

Exclusion criteria:

1. Prior therapy with an anti-PD-1, anti-PD-L1 or anti-PD-L2 agent or with an agent directed to another stimulatory or co-inhibitory T-cell receptor (eg, CTLA-4, OX-40, CD137)
2. Has a diagnosis of low grade or mucinous ovarian cancer
3. Has a diagnosis of immunodeficiency or is receiving systemic steroid therapy (dose exceeding 10 mg daily of prednisone equivalent) or any other form of immunosuppressive therapy within 7 days prior to the first dose of trial treatment (n.b. the use of physiologic doses of corticosteroids may be approved after consultation with UCL CTC). Use of inhaled steroids is permitted.
4. Has a known history of active TB (Bacillus Tuberculosis)
5. Has known history of Hepatitis B (defined as Hepatitis B surface antigen [HBsAg] reactive) or known Hepatitis C virus (defined as HCV RNA [qualitative] is detected)*
6. Has a known history of Human Immunodeficiency Virus (HIV)

7. Has received prior systemic anti-cancer therapy including investigational agents within 4 weeks (could consider shorter interval for kinase inhibitors or other short half-life drugs) prior to registration.

   Note: Participants must have recovered from all AEs due to previous therapies to ≤Grade 1 or baseline. Participants with ≤Grade 2 neuropathy may be eligible

8. Has received prior radiotherapy within 2 weeks of start of study treatment. Participants must have recovered from all radiation-related toxicities, not require corticosteroids, and not have had radiation pneumonitis. A 1-week washout is permitted for palliative radiation (a maximum of 2 weeks radiotherapy is allowed) to non-CNS disease
9. Patients with concurrent or previous malignancy within the last 5 years (except Stage I grade 1 endometrial cancer; in situ cervical cancer; DCIS of the breast) that could compromise assessment of the primary or secondary endpoints of the trial
10. Active central nervous system (CNS) metastases and/or carcinomatous meningitis; patients with previously treated brain metastases may participate
11. Has active autoimmune disease that required systemic treatment in past 2 years (i.e. with use of disease modifying agents, corticosteroids (at doses >10mg prednisolone daily or equivalent) or immunosuppressive drugs) except vitiligo or resolved childhood asthma/atopy. Replacement hormone therapy (e.g. levothyroxine, insulin, or physiologic corticosteroid replacement therapy for adrenal or pituitary insufficiency, etc.) is permitted
12. Has a corrected serum calcium of >1.5 x ULN despite maximal antihypercalcaemic therapy
13. Has a history of (non-infectious) pneumonitis/ interstitial lung disease that required steroids or has current pneumonitis or has a history of interstitial lung disease
14. Has a newly diagnosed venous thrombotic event (e.g. PE, DVT) untreated with anticoagulation. Patients must have received at least 14 days of anticoagulation for a new thrombotic event and be suitable for continued therapeutic anticoagulation during trial participation. Patients are excluded if they have a history of arterial thrombosis
15. Has an active infection requiring systemic therapy
16. Has symptoms of bowel obstruction in the past three months
17. Any serious and/or unstable pre-existing medical, psychiatric or other condition that, in the treating clinician's judgement could interfere with patient safety or obtaining informed consent
18. Has known psychiatric or substance abuse disorders that would interfere with cooperation with the requirements of the trial
19. Is pregnant or breastfeeding, or expecting to conceive children within the projected duration of the trial, starting with the screening visit through to 4 months after the last dose of trial treatment
20. Has received a live vaccine within 30 days of planned start of study treatment. Examples of live vaccines include, but are not limited to, the following: measles, mumps, rubella, varicella/zoster (chicken pox), yellow fever, rabies, Bacillus Calmette-Guérin (BCG), and typhoid vaccine. Seasonal influenza vaccines for injection are generally killed virus vaccines and are allowed; however, intranasal influenza vaccines (eg, FluMist®) are live attenuated vaccines and are not allowed.

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: Treatment; Maintenance treatment with trial drug pembrolizumab; 200mg IV every 21 days until progression, unacceptable toxicity, patient or clinician decision.	Drug: Pembrolizumab; Intravenous infusion; Other Names: Keytruda

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Progression-Free Survival Rate at 6 Months From Start of Study Treatment (Maintenance Pembrolizumab)	Progression is defined using Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1), with at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm. The appearance of one or more new lesions or unequivocal progression of existing non-target lesions is also considered progression. Using A'Hern's single-stage phase II design with a one-sided 5% significance level and 80% power, ≥16 participants needed to be alive and progression-free at 6 months for the protocol aim to be reached.	6 months from start of study treatment (maintenance pembrolizumab)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Progression Free Survival at 6 Months Measured From the Start of Pre-trial Weekly Paclitaxel	Progression Free Survival at 6 months was measured from the start of pre-trial weekly paclitaxel using Kaplan-Meier estimates with censoring on the date of last study assessment.	6 months from the start of weekly previously administered standard of care paclitaxel to the date of first progression or death from any cause.
Overall Survival	Kaplan-Meier estimates were used to analyse overall survival from the start of maintenance pembrolizumab to the date of death from any cause.	From start of study treatment until the date of death from any cause or end of study whichever came first, assessed up to 50 months.
Disease Response	Disease response as per Response Evaluation Criteria in Solid Tumours (RECIST) version 1.1, using CT scan assessment: Complete Response- disappearance of all target lesions; Partial Response at least a 30% decrease in the sum of diameters of target lesions, taking as reference the baseline sum diameters; Progressive Disease - at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study (Note: the appearance of one or more new lesions and unequivocal progression is also considered progression); Stable Disease - neither sufficient shrinkage to qualify for partial response nor sufficient increase to qualify for progressive disease, taking as reference the smallest sum diameters while on study.	Before cycle 1, cycle 4 and cycle 7 of study treatment, then every 12 weekly (4 cycles) during treatment until progression up to 24 months.
Treatment Compliance	The number and percentage of patients who stopped treatment due to any reason other than disease progression were analysed. A median of 3.5 cycles of pembrolizumab were given. Nineteen participants stopped due to disease progression and one participant discontinued due to a treatment related adverse event.	Date of first study treatment administration dose until the date of last administration dose of study treatment, assessed for duration of study treatment in all participants: up to 42 months.

Collaborators and Investigators

• Sponsor: University College, London
• Collaborators: Merck Sharp & Dohme LLC
• Investigators: Study Chair: UCL Cancer Trials Centre, UCL

Study record dates

Study Major Dates

• Study Start (Actual): May 16, 2019
• Primary Completion (Actual): December 3, 2025
• Study Completion (Actual): December 3, 2025

Study Registration Dates

• First Submitted: February 6, 2018
• First Submitted That Met QC Criteria: February 6, 2018
• First Posted (Actual): February 13, 2018

Study Record Updates

• Last Update Posted (Actual): May 20, 2026
• Last Update Submitted That Met QC Criteria: May 18, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: platinum-resistant
• Additional Relevant MeSH Terms: Urogenital Diseases; Genital Diseases; Endocrine System Diseases; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Genital Diseases, Female; Endocrine Gland Neoplasms; Ovarian Diseases; Adnexal Diseases; Genital Neoplasms, Female; Gonadal Disorders; Fallopian Tube Diseases; Ovarian Neoplasms; Fallopian Tube Neoplasms; Antineoplastic Agents; Antineoplastic Agents, Immunological; pembrolizumab
• Other Study ID Numbers: UCL/17/0629

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: No
• Studies a U.S. FDA-regulated device product: No