CEO & Co-Founder
Caitlyn Miller, PhD, is CEO and Co-Founder of TwoStep Therapeutics and is dedicated to the company’s mission of bringing innovative targeted therapies to patients. Dr. Miller received her PhD in Bioengineering from Stanford University in the labs of Dr. Carolyn Bertozzi and Dr. Jennifer Cochran. During her PhD and postdoctoral work, Dr. Miller played a pivotal role in advancing technology that is now integrated into TwoStep’s therapeutic pipeline. Dr. Miller then joined the Stanford Innovative Medicines Accelerator as an Entrepreneur-In-Residence, where she spearheaded the efforts to spin out TwoStep Therapeutics.
VP, Clinical
Joy Geallis, is VP, Clinical at TwoStep Therapeutics, bringing over a decade of expertise in advancing programs from preclinical research to Phase I-III trials. Her patient-focused approach and proven track record in clinical development encompass trial design, execution, and regulatory filings. Prior to joining TwoStep Therapeutics, Ms. Geallis served as Vice President of Clinical at Immunitas Tx, where she successfully led the development of the lead program into a Phase I/II trial. She has also held pivotal roles at Astellas, Xeris Biopharma, and Northwestern University, where she demonstrated her expertise in strategic planning, cross-functional collaboration, and driving progress in clinical programs.
VP, Radiopharmaceutical Clinical Development
Nicolas Salem, PhD, is VP, Radiopharmaceutical Clinical Development at TwoStep Therapeutics. Dr. Salem joined TwoStep in April 2026 to lead the clinical development of the company’s radioligand program and brings over 15 years of experience in drug discovery and development in both biotech and large pharmaceutical companies. As a clinical imaging expert with a patient-centric focus and a deep commitment to operational excellence, Dr. Salem has contributed to the design and conduct of multiple Phase 0-4 trials for small molecule, immuno-oncology and therapeutic radiopharmaceuticals. Prior to joining TwoStep, Dr. Salem served as Executive Director, Clinical Imaging at Mariana Oncology, a Novartis company, where he designed and oversaw the conduct of Ph0 and Ph1 studies in support of two radiopharmaceutical programs. Dr. Salem also held a Senior Director, Clinical Imaging role at Bayer and scientist roles at Biogen and Takeda Pharmaceuticals. Dr. Salem received his PhD in Biomedical Engineering from Case Western Reserve University.
Director, R&D Operations
Yash Agarwal, PhD, is Director, R&D Operations at TwoStep Therapeutics, leading preclinical research and operations at TwoStep Therapeutics. As a member of the founding team, Yash brings extensive expertise and leadership to the organization. Prior to his role at TwoStep, Yash contributed significantly to advancing cell therapies at GentiBio. Yash’s journey in biological engineering began during his doctoral studies at Massachusetts Institute of Technology (MIT), where he developed an innovative approach to improve the efficacy and safety of cancer immunotherapies in the labs of Dr. Dane Wittrup and Dr. Darrell Irvine. His research led to notable publications and patent involvement, establishing him as a leader in the field. With a steadfast commitment to advancing cutting-edge therapies for human diseases, Yash Agarwal continues to drive innovation and make impactful contributions to the field of biotechnology.
Senior Scientist
Caleb Perez, PhD, is a Senior Scientist at TwoStep Therapeutics and is passionate about the clinical translation of novel therapeutics that impact the lives of cancer patients. Caleb has worked toward this goal throughout his career, beginning with his work as a Fulbright Scholar at the Ecole Polytechnique Federale de Lausanne (EPFL) in Switzerland, where he studied new modalities for dendritic cell cancer vaccines. During his doctoral studies in Biological Engineering at MIT, he worked under Dr. Michael Birnbaum to engineer high-throughput platforms to optimize T cell-based immunotherapies. At TwoStep, Caleb continues to cement his commitment to advancing impactful cancer treatments by supporting the preclinical research and development of TwoStep’s therapeutic pipeline.
Co-Founder
Jennifer Cochran, PhD, is a Co-Founder of TwoStep Therapeutics and is the Addie and Al Macovski Professor of Bioengineering and the Senior Associate Vice Provost for Research at Stanford University. She is a founding member of the Stanford Bioengineering Department and served as its Chair from 2017 to 2022. Her research expertise and translational interests span protein-based drug discovery and development for applications in oncology and regenerative medicine. Dr. Cochran’s lab originally engineered the innovative tumor-targeting peptide integral to TwoStep’s platform. Dr. Cochran is a serial innovator and brings extensive company formation and entrepreneurial experience, having co-founded several biotech companies and Red Tree Venture Capital.
Co-Founder
Carolyn Bertozzi, PhD, is a Co-Founder of TwoStep Therapeutics and is the Anne T. and Robert M. Bass Professor of Chemistry at Stanford University and an Investigator of the Howard Hughes Medical Institute. She was awarded the 2022 Nobel Prize in Chemistry for the invention of bioorthogonal chemistry and is a world leader in antibody-drug conjugate technology. Dr. Bertozzi is an elected member of the National Academy of Medicine, the National Academy of Sciences, and the National Academy of Engineering and has been awarded the Welch Award in Chemistry, the Solvay Prize, the Wolf Prize, the Heineken Prize for Biochemistry and Biophysics and a MacArthur Foundation Fellowship, among many others. Her commitment to innovation extends beyond academia, as evidenced by her board memberships at Alnylam Pharmaceuticals, OmniAb and Xaira Therapeutics, and her previous service on the board of Lilly.
Co-Founder
Ronald Levy, MD, is a Co-Founder of TwoStep Therapeutics and is a medical oncologist and Professor of Medicine at Stanford University. Dr. Levy is a pioneer in the field of cancer immunotherapy. He was the first to successfully treat cancer with a monoclonal antibody, and went on to help develop Rituximab (Rituxan®), the first FDA-approved monoclonal antibody for cancer, which is still widely used to treat lymphoma today. Dr. Levy currently serves as the Associate Director of Translational Science for the Stanford Cancer Institute and previously served as the Chief of the Division of Oncology at Stanford University School of Medicine.
Strategic Advisor
Michael Ostrach, is a Strategic Advisor of TwoStep Therapeutics. He brings over 40 years of experience managing public, private, commercial and research-based biotechnology companies, including the initiation and execution of numerous public and private financings, partnerships and acquisitions. Mr. Ostrach previously served as the Chief Financial Officer, Chief Business Officer and General Counsel at Dynavax Technologies Corporation, a commercial biopharmaceutical company with a marketed vaccine. Earlier in his career, Mr. Ostrach held leadership roles at several biotechnology companies including Threshold Pharmaceuticals, Inc., Kosan Biosciences, Inc., Chiron Corporation and Cetus Corporation. Mr. Ostrach obtained a J.D. from Stanford Law School and a B.A. from Brown University.
