Former Nimbus Therapeutics CEO brings proven expertise scaling platform biotech companies and executing key strategic partnerships as Strand advances its clinical pipeline

Strand Therapeutics, a leader in next-generation mRNA-based therapeutics, today announced that former Nimbus Therapeutics CEO, Jeb Keiper, has joined Strand’s Board as an independent Director to bolster the company's continued growth and business development capabilities to scale its programmable mRNA platform. From preclinical R&D innovation and clinical development to global BD&L, Mr. Keiper brings proven experience building and scaling biotechnology companies through multiple clinical programs and strategic partnerships.

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Jeb Keiper, Independent Board Director

"We're building the infrastructure of programmable genetic medicines, and bringing Jeb on at this stage reflects the trajectory we're on,” said Jake Becraft, PhD, Co-founder and Chief Executive Officer of Strand Therapeutics. “He's built multi-billion dollar platform biotechs, structured transformative partnerships, and navigated complex growth stages. That strategic perspective will be invaluable as we scale our platform and advance multiple clinical programs."

Mr. Keiper joins as an independent Board Member following his tenure as Chief Executive Officer of Nimbus Therapeutics, where he built the company over more than a decade. Serving in multiple leadership roles at Nimbus, including Chief Business Officer, Chief Financial Officer, and ultimately CEO, Mr. Keiper oversaw the discovery and development of four programs into clinical testing across a range of indications, raised over $650M in equity funding, executed deals worth over $7B, and returned over $4.1B in gains to equity holders. Prior to Nimbus, he spent nearly ten years at GSK in various business development leadership roles.

“Strand’s vision to use the demonstrated power of mRNA with precisely programmed expression to any specific cell type has the potential to be transformative for the treatment of many diseases. Strand has already shown patient success with its first clinical program STX-001, with even more advanced programs coming to the clinic next year and beyond. I deeply admire this company the founders have built, and am delighted to join as Strand’s first independent Board Director,” said Mr. Keiper. “I look forward to helping Jake and the Strand team achieve their ambitious vision.”

Currently, Mr. Keiper serves on the boards of Cardurion Pharmaceuticals and Life Science Cares in Boston. He holds two BS degrees, one in Chemistry and one in Chemical Engineering; an MS in Chemical Engineering from the Massachusetts Institute of Technology (MIT); and an MBA from the MIT Sloan School of Management with a joint program in Biomedical Enterprises with the Harvard Medical School.

This announcement continues Strand’s significant 2025 momentum. In August 2025, the company announced the close of a $153M Series B financing led by Kinnevik with the participation of multiple large pharma investors. The company also presented first-in-human Phase 1 data at the 2025 ASCO Annual Meeting, demonstrating multiple clinical responses in patients with advanced solid tumors who had exhausted other treatment options. With ongoing clinical trials in solid tumors, another trial launching in mid-2026, and rapid expansion into CAR-T therapy, the company is demonstrating the breadth and versatility of its platform. In early November 2025, Strand announced the promotion of Prashant Nambiar, MBA, PhD, as Chief Scientific Officer and the appointment of Ethan Cash as Senior Vice President of Program Management and Strategy. The appointments of Mr. Keiper, Dr. Nambiar and Mr. Cash position Strand to achieve anticipated milestones and advance its mission of integrating genetic medicines into the core of modern therapeutics.

About Strand Therapeutics

Strand Therapeutics is leading the next generation of programmable mRNA therapies: where synthetic biology meets programmable biology to unlock the full potential of gene regulation and delivery inside the body. Unlike traditional mRNA technologies, Strand’s platform programs RNA to think, enabling logic-controlled expression, precision delivery, and unprecedented control over therapeutic outcomes.

Born out of MIT and led by world-class synthetic biologists, Strand is building the infrastructure to create medicines that respond to disease signals in real-time. With its computationally-driven design engine, self-amplifying/circular RNA modalities, and mRNA-only genetic circuits, the company is pioneering a new therapeutic modality poised to disrupt immuno-oncology, cell therapy, autoimmune diseases, and beyond.

Strand’s lead pipeline program, STX-001, is already in the clinic showing unprecedented response rates in late stage “salvage” cancer patients, with multiple patients showing RECIST responses. Strand’s modular platform opens a broad horizon of partnership and licensing opportunities. Strand isn’t just another mRNA company: it’s the operating system for the programmable medicines of tomorrow. Follow us on LinkedIn and on X at @strandtx.

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"We're building the infrastructure of programmable genetic medicines, and bringing Jeb on at this stage reflects the trajectory we're on,” said Jake Becraft, PhD, Co-founder and Chief Executive Officer of Strand Therapeutics.