Director / Senior Director, Toxicology

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Department: DMPK / Toxicology

Location: South San Francisco, California, United States

Summary:  We are seeking an experienced, creative, and highly motivated expert with industry experience in toxicology focused on discovery and development of small molecule therapeutics. This position will be responsible for designing and executing toxicology, safety pharmacology, and other safety studies to support both preclinical and clinical projects.  The position will work closely with Sr. Leadership in both Research and Development to facilitate the advancement of Assembly’s portfolio of Novel HBV therapeutics.

Key Responsibilities include:

  • Lead scientific and technical efforts to support non-clinical safety evaluation of drug candidates across Assembly’s R&D portfolio from pre-IND through Phase 3 and beyond
  • Provide scientific guidance on chemical lead optimization programs and work in close collaboration with Medicinal Chemistry, DMPK, and Biologists to optimize the safety properties of candidate drugs
  • Provide scientific guidance and support to colleagues in Clinical, Regulatory, Manufacturing, and Project Management to support drug development.
  • Identification and management of external CROs to meet toxicology and safety pharmacology needs including execution of studies and completion of study reports to support the R&D portfolio
  • Interpret safety pharmacology and toxicology/toxicokinetic study data write toxicology sections of regulatory documents
  • Establish safety margins to inform the clinical and regulatory strategy
  • Preparation of budgets for toxicology needs of R&D portfolio

Preferred Qualifications include:

  • The candidate should have a Ph.D. or equivalent in pharmacology, toxicology, or a related discipline with of 10+ years of industry experience. Candidates at the senior level should have additional years of industry experience.
  • Extensive experience with preclinical small molecule drug development including designing, monitoring, and interpreting non-GLP and GLP toxicology studies and data
  • In-depth understanding of GLP regulations and related US and ex-US regulatory pharm/tox regulatory guidance
  • Ability to work effectively with CROs and consultants
  • Strong written, verbal, and interpersonal communications skills including ability to communicate scientific information clearly and effectively
  • The candidate should be self-motivated, with a track record of productivity, demonstrated leadership, possess effective interpersonal skills and be team oriented.

About Assembly Bio

Assembly Biosciences (NASDAQ: ASMB) is a clinical stage biopharmaceutical company with cutting-edge therapeutics potentially capable of improving millions of lives around the world.  We pride ourselves on creating a culture and work environment that is scientifically driven, ambitious, and collaborative. We encourage diversity of thought that leads to great innovation and are looking to add great people to our dynamic team who are driven to transform the lives of patients.  We are currently focused on the development of two intelligently designed, scientifically novel clinical platforms:

An HBV program intent on creating a new class of oral therapeutics to finally cure hepatitis B.  Our program is built on ingenuity, vision and experience and has the potential to improve cure rates for individuals with chronic hepatitis B (HBV) in our lifetime. Our strong scientific expertise in discovering small molecules targeting the HBV core protein has made us a leader in the field.

A Microbiome program of potentially life-changing oral live biotherapeutics to transform the treatment of an entire range of diseases linked to the microbiome.  We believe our Microbiome platform represents a best in class approach, translating naturally evolved, bacteria-host pharmacological interactions into rationally selected, live oral biotherapeutics.

Assembly Bio has a strong balance sheet and is well-positioned to advance our innovative research and potential medicines in HBV-cure and the Microbiome.  Headquartered in South San Francisco, CA, Assembly Bio also operates a microbiome manufacturing facility in Groton, CT, and has offices in China. 

AAP/EEO Statement

Assembly Biosciences is an Equal Opportunity Employer and prohibits discrimination and harassment of any kind. We are committed to the principle of equal employment opportunity for all employees and to providing employees with a work environment free of discrimination and harassment. All employment decisions are based on business needs, job requirements and individual qualifications, without regard to race, color, religion or belief, national, social or ethnic origin, sex (including pregnancy), age, physical, mental or sensory disability, HIV status, sexual orientation, gender identity and/or expression, marital, civil union or domestic partnership status, past or present military service, family medical history or genetic information, family or parental status, or any other status protected by the laws or regulations in the locations where we operate. We will not tolerate discrimination or harassment based on any of these characteristics.


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