Associate Director, Toxicology

Protagonist Therapeutics Inc.

Posted on: June 11, 2026

Closing: July 11, 2026

Salary: 185,000.00 - 205,000.00 per year

Job Description

Associate Director, Toxicology, Nonclinical Development (Program Toxicologist)

Position Description:

Protagonist Therapeutics is seeking a talented, highly motivated professional to join the Toxicology, Nonclinical Development team as Associate Director Toxicology, Nonclinical Development (Program Toxicologist). This role will lead and manage CRO and consultant activities that support drug research and development across the PTGX pipeline. The successful candidate will be responsible for developing nonclinical toxicology strategies, overseeing GLP and non-GLP studies, preparing toxicology components of regulatory submissions, and responding to inquiries from regulatory authorities. This position will report to the Senior Vice President, Toxicology, Nonclinical Development.

Responsibilities:

  • Serve as a self-directed toxicology leader and key member of a dynamic team supporting PTGX drug discovery and development programs.

    Independently develop phase-appropriate nonclinical toxicology strategies for PTGX pipeline molecules and represent toxicology on cross-functional project teams.
  • Design, revise, and finalize nonclinical toxicology study protocols, study designs, data analyses, and reports, including plans that support first-in-human and later-stage clinical development.
  • Prepare and critically review nonclinical toxicology sections for IND, CTA, NDA, and other regulatory submissions, ensuring alignment with applicable US and ex-US regulatory expectations.
  • Identify, evaluate, and resolve program-specific toxicology issues in collaboration with the supervisor, project teams, CROs, consultants, and other subject-matter experts.
  • Critically review and edit CRO nonclinical toxicology and related study reports, including pharmacology, ADME, PK/TK, safety pharmacology, and pathology reports; analyze and interpret data; and coordinate report finalization.
  • Ensure study documentation and regulatory deliverables are scientifically sound, timely, and consistent with global regulatory and compliance requirements.
  • Manage and monitor GLP and non-GLP nonclinical studies conducted at CROs in accordance with PTGX vendor management SOPs and policies, ensuring quality, timelines, and regulatory compliance are met or exceeded.
  • Provide clear analysis, interpretation, and visualization of nonclinical toxicology and related data for internal communications, program team presentations, regulatory interactions, and decision-making.
  • Maintain current knowledge of relevant scientific literature, methodologies, regulatory guidance, and emerging best practices applicable to PTGX pipeline products and nonclinical development programs.

Qualifications:
  • PhD or DVM in biological sciences, toxicology, pharmacology, or a related discipline.
  • DABT board certification is preferred.
  • Minimum of 5-10 years of relevant drug development experience, preferably in the biotechnology or pharmaceutical industry.
  • Demonstrated experience developing and executing nonclinical toxicology strategies that support IND-enabling studies, first-in-human clinical trials, and later-stage development programs.
  • Strong working knowledge of Good Laboratory Practice regulations and relevant FDA, ICH, OECD, EMA, and other global nonclinical safety guidelines.
  • Experience in preclinical development, toxicology, nonclinical pharmacology, drug metabolism, pharmacokinetics, and toxicokinetics.
  • Proven ability to manage CROs, consultants, and external academic or industry collaborators, including oversight of study design, budgets, timelines, monitoring, data review, and final reports.
  • Broad and integrated understanding of pharmacology, toxicology, DMPK, safety pharmacology, pathology, and translational safety assessment.
  • Excellent verbal and written communication skills, with the ability to build strong working relationships with internal colleagues, cross-functional teams, external vendors, and consultants.
  • Strong scientific background, preferably demonstrated through peer-reviewed publications, regulatory writing experience, or presentations in relevant medical and life science forums.
  • Excellent decision-making, complex problem-solving, critical thinking, data analysis, and data interpretation skills.
  • Highly motivated, flexible, and proactive self-starter who takes ownership of new tasks and delivers high-quality results with limited supervision.
  • Demonstrated ability to be productive and successful in a fast-paced, matrixed, and multi-tasking work environment.

The base pay range for this position at commencement of employment is expected to be between $185K and $205K / year; however, base pay offered may vary depending on multiple individualized factors, including market location, job-related knowledge, skills, and experience.

Protagonist Therapeutics is a discovery through late-stage development biopharmaceutical company. The Company's proprietary peptide technology platform enables de novo discovery of peptide therapeutics. Two novel peptides derived from Protagonist's proprietary discovery platform are at or near commercialization. ICOTYDE™ (icotrokinra) is approved in the U.S. for the treatment of moderate-to-severe plaque psoriasis in adults and pediatric patients 12 years of age and older who weigh at least 40 kg who are candidates for systemic therapy or phototherapy. ICOTYDE is the first and only targeted oral peptide that precisely blocks the Interleukin-23 receptor (IL-23R) licensed to Janssen Biotech, Inc.,a Johnson & Johnson company. ICOTYDE was jointly discovered by Protagonist and Johnson & Johnson scientists, with Protagonist having primary responsibility for the development of ICOTYDE through Phase 1, and Johnson & Johnson assuming responsibility for further development and commercialization. An NDA for rusfertide, a first-in-class hepcidin mimetic peptide that is being co-developed with Takeda Pharmaceuticals pursuant to a worldwide license and collaboration agreement entered in 2024, is under priority review with the FDA. Protagonist holds an option to co-commercialize rusfertide in the U.S. through a 50/50 profit and loss share structure or can opt-out of this structure. The Company also has a number of preclinical stage drug discovery programs addressing clinically and commercially validated targets including an oral IL-17 peptide antagonist, obesity dual and triple agonists, an oral hepcidin functional mimetic, and the recently announced IL-4 and amylin programs.

More information on Protagonist, its pipeline drug candidates, and clinical studies can be found on the Company's website at https://www.protagonist-inc.com.

Protagonist Therapeutics Inc.

Posted on: June 11, 2026

Closing: July 11, 2026

Salary: 185,000.00 - 205,000.00 per year

Career Focus: Toxicology

This role is part of a curated selection of life science opportunities featured on Xtalks. Employers may request edits or removal here.

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