Principal Scientist II, Immunology

Company Overview

ModeX Therapeutics, an OPKO Health company, is the leading clinical-stage biopharmaceutical company developing unique and proprietary-multispecific therapeutics. Its MSTAR platform unites the power of multiple biologics in a single molecule to create multispecific antibodies that bind four or more targets with unprecedented versatility and potency for complex diseases. Its promising first-in-class immunology pipeline includes candidates against immune diseases, including cancer (both solid and hematologic tumors), immune impairment, as well as several of the world’s most pressing viral threats.

Its founding team includes globally recognized medical innovators with proven track records of delivering breakthroughs for patients. ModeX is based in Weston, Massachusetts. For more information, please visit

ModeX Therapeutics is seeking a highly skilled and motivated Principal Scientist II, Immunology to play a leading scientific role in the discovery and preclinical development of novel multispecific biologics for immuno-oncology and immunology/inflammation indications. The successful candidate will play a central role across the full discovery lifecycle; from identifying therapeutic concepts and designing differentiated multispecific molecules through mechanistic characterization, candidate selection, and advancement into IND-enabling development.

This individual will provide scientific and strategic leadership, work closely with cross-functional teams, and help translate innovative biology into IND-ready therapeutic candidates.

This is an exciting opportunity to contribute to the development of next-generation immune therapies in a fast-paced and collaborative biotechnology environment.

• Provide scientific and strategic leadership for multispecific therapeutic programs in immuno-oncology and immunology/inflammation, from early ideation through IND-enabling development.
• Identify and evaluate novel targets, target combinations, mechanisms, and multispecific formats aligned with the company’s research and pipeline strategy.
• Develop differentiated therapeutic concepts and define clear biological hypotheses, candidate profiles, and experimental strategies.
• Lead target validation, molecule characterization, lead optimization, and candidate-selection activities.
• Design and oversee robust in vitro, ex vivo, and in vivo studies to evaluate mechanism of action, potency, selectivity, target engagement, pharmacology, and translational relevance.
• Establish and apply screening cascades and decision criteria to prioritize molecules and advance programs through key stage gates.
• Generate integrated data packages supporting preclinical development, IND-enabling studies, regulatory documentation, and external partnering activities.
• Identify scientific, technical, and translational risks and develop appropriate mitigation strategies.
• Collaborate closely with protein engineering, antibody discovery, translational sciences, CMC, clinical, regulatory, and business-development teams.
• Lead, mentor, and develop scientists and research associates while fostering a collaborative, inclusive, and high-performing team culture.
• Ensure scientific rigor, data quality, and clear documentation across experimental design, data interpretation, and program decision-making.
• Monitor emerging scientific and competitive developments and incorporate relevant insights into research strategy and portfolio planning.
• Present program strategies, results, recommendations, and risks to research teams, senior leadership, collaborators, and external partners.

• Master’s Degree in Immunology, Immuno-Oncology, Cancer Biology, or a related discipline, with 13+ years of relevant research experience, including at least 7+ years in a biotech or pharmaceutical R&D environment. Ph.D. preferred.
• Deep expertise in immunology and immuno-oncology disease biology.
• Demonstrated track record of advancing biologic therapeutic programs from early discovery through preclinical development and IND-enabling activities.
• Experience developing multispecific antibodies, immune-cell engagers, antibody-based therapeutics, or…