Galinpepimut-S (GPS): an investigational agent for the treatment of acute myeloid leukemia

ABSTRACT

Introduction: Acute myeloid leukemia (AML) is a disorder wherein clonal expansion of undifferentiated myeloid precursors results in compromised hematopoiesis and bone marrow failure. Even though numerous AML patients respond to induction chemotherapy, relapse is common and hence new therapeutic approaches are needed. Wild-type Wilms tumor gene (WT1) is greatly expressed in numerous blood disorders and so this has led to development of galinpepimut-S, a WT1 vaccine as a modality to maintain remission in patients with AML.

Areas covered: We summarize and examine the structure, key features, safety, and efficacy data of galinpepimut-S (GPS) for AML. GPS has been shown to be safe and tolerable in phase 1 and phase 2 studies and is now being evaluated in a phase 3 study.

Expert opinion: Given the unmet need in the treatment of relapsed and refractory AML, especially among the elderly and patients with comorbidities who are not fit enough to undergo traditional salvage treatments, GPS could potentially fill the gap for this subset of patients. Future clinical trials utilizing GPS in second complete remission 2 (CR2) compared to best available therapy in AML and in combination with other immunotherapeutic agents (like pembrolizumab) for treatment for various malignancies are underway.

KEYWORDS:

• AML
• WT1 peptide
• Galinpepimut-S
• peptide vaccination
• acute myeloid leukemia

Article highlights

• The WT1 protein was rated as an immunologic target by a National Cancer Institute prioritizing venture.

• Galinpepimut-S (GPS) is a sophisticated, multivalent, heteroclitic WT1 peptide vaccine. It is non-HLA-restricted and is designed to induce CD8+ and CD4+ immunoresponses.

• GPS is well tolerated and has been reported to show efficacy in AML post first complete remission (CR1) and second complete remission (CR2).

• The most common adverse events of the vaccine are grade 1 or 2 injection site reactions.

• A large randomized study, REGAL is underway to study GPS as maintenance strategy in CR2 compared to investigators choice of best available therapy in non-transplant candidates.

• GPS can potentially be studied in the future as both monotherapy maintenance therapy and combination with checkpoint inhibitors and other immuno-Oncology therapies.

Acknowledgments

Editorial assistance was provided by the Moffitt Cancer Center’s Scientific Editing Department by Dr. Paul Fletcher & Daley Drucker. No compensation was given beyond their regular salaries.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial relationships or otherwise to disclose.

Declaration of interest

J Pinilla-Ibarz has received fees from intellectual property in relation with GPS, has a Consultancy role with Novartis, Pfizer, Takeda, Janssen, Abbvie, Sellas Therapeutics and AstraZeneca and is on the Speaker bureau for AstraZeneca, Janssen, Abbvie and Takeda. C TalatI holds Consultancy roles with Novartis, Abbvie, BMS, and Pfizer and is on the Speakers Bureau for Astellas and Jazz. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Additional information

Funding

This paper was not funded.