Assistant Director/Associate Director, Toxicology

Ionis Pharmaceuticals, Inc.; Carlsbad, Northern (CA, KY); Hybrid; USD 143,000 - 255,000; Full time

Benefits offered by this job

Benefits package

Job summary

Ionis Pharmaceuticals, Inc. in Carlsbad, CA, seeks a Toxicologist to lead nonclinical safety assessments in the Preclinical Development Department. You will work on-site in Carlsbad, provide strategic toxicology input, and guide cross-functional teams on program advancement.

The candidate will design and interpret studies, manage CROs, and draft regulatory sections while representing Ionis with regulatory authorities. A Ph.D. or equivalent and 3–6+ years in industry are expected.

Qualifications

• Master’s or Doctoral degree in Toxicology or a related life sciences discipline.
• At least 6 years (Master’s) or 3 years (Ph.D.) of nonclinical safety experience in pharma/biotech.
• Excellent analytical, organizational, and communication skills.
• Experience managing outsourced studies and working with CROs, including protocol and report development or review, and timeline management.
• Experience generating, integrating, reviewing, and interpreting toxicology data.
• Experience authoring regulatory documents such as IBs, INDs, CTDs, and health authority submissions.
• Demonstrated ability to work effectively in a matrixed environment, influencing across teams.
• Commitment to lifelong learning and professional development.

Responsibilities

• Serve as the nonclinical safety representative on cross-functional project teams to support candidate selection and risk assessment.
• Design, oversee, and interpret nonclinical pharmacology and toxicology studies (non-GLP and GLP).
• Manage outsourced toxicology studies at CROs, including protocol and report review and timeline management.
• Synthesize pharmacology, toxicology, clinical pathology, and PK/TK data for integrated safety assessments.
• Develop nonclinical toxicology and regulatory strategies for assigned programs.
• Author/review nonclinical sections of regulatory documents (IBs, INDs, NDAs, DSURs) and liaise with authorities.
• Assess mechanisms of toxicity to determine human relevance and development impact.
• Communicate key nonclinical findings and development implications to project teams and governance committees.
• Represent Ionis externally at meetings, consortia, and professional societies; contribute to publications.

Skills

Analytical skills

Organizational skills

Communication skills

Education

Master’s or Doctoral degree in Toxicology or related life sciences

Tools

CRO oversight

Job description

Job Category: Development - Ionis

Requisition Number: IONIS004030

• Posted : September 2, 2026
• Full-Time

Locations

Showing 1 location

Description

Headquartered in Carlsbad, California, and with offices in Boston, Massachusetts, and Dublin, Ireland, Ionis has been at work for more than three decades discovering medical breakthroughs that have redefined life for people with serious diseases. We’re pioneers in RNA-targeted medicines, and our platform continues to revolutionize drug discovery and transform lives for patients with unmet needs. With multiple marketed medicines and a leading pipeline in neurology, cardiology and select areas of high patient needs, we continue to drive innovation in RNA therapies in addition to advancing new approaches in gene editing to provide greater value to patients and are well positioned financially to deliver on our strategic goals.

At Ionis, we pride ourselves on cultivating a challenging, motivating and rewarding environment that fosters innovation and scientific excellence. We know that our success is a direct result of the exceptional talents and dedication of our employees.

With an unprecedented opportunity to change the course of human health, we look to add diverse individuals, skill sets and perspectives to our exceptional team. We continue to invest time, money and energy into making our onsite, hybrid and remote work environments a place where solid and lasting relationships are built and where our culture and employees can thrive.

We’re building on our rich history, and we believe our greatest achievements are ahead of us. If you’re passionate about the opportunity to have meaningful impact on patients in need, we invite you to apply and join us. Experience and contribute to our unique culture while you develop and expand your career!

ASSISTANT DIRECTOR/ ASSOCIATE DIRECTOR, TOXICOLOGY

SUMMARY:

Ionis is seeking a talented and highly motivated Toxicologist to join the Preclinical Development Department and provide scientific leadership in the nonclinical safety assessment of drug candidates. The department is composed of highly collaborative scientists and offers a supportive environment that fosters professional growth and continuous learning. The expectation will be for this person to work on site in Carlsbad, CA.

RESPONSIBILITIES:

• Serve as the nonclinical safety representative on cross-functional project teams, providing strategic toxicology input to support candidate selection, risk assessment, and program advancement
• Design, oversee, and interpret non-GLP and GLP nonclinical pharmacology and toxicology studies
• Manage outsourced toxicology studies at CROs, including study design, protocol and report review, issue resolution, and timeline management
• Drive integrated nonclinical safety assessments by synthesizing pharmacology, toxicology, clinical pathology, and TK/PK data
• Develop nonclinical toxicology and regulatory strategies for assigned programs
• Author and review nonclinical sections of regulatory documents, including Investigator's Brochures, INDs, NDAs, DSURs, and related submissions, and represent Ionis in interactions with regulatory authorities
• Assess mechanisms of toxicity to determine human relevance and development impact
• Communicate key nonclinical safety findings, risk assessments, and development implications to project teams and governance committees
• Represent Ionis externally through scientific meetings, industry consortia, working groups, and professional societies
• Contribute to scientific publications in high-impact, peer-reviewed journals

REQUIREMENTS:

• Master’s or Doctoral degree in Toxicology or a related life sciences discipline
• At least 6 years (Master’s degree) or 3 years (Ph.D.) of experience in nonclinical safety within the pharmaceutical or biotechnology industry
• Excellent analytical, organizational, and communication skills
• Experience managing outsourced studies and working with CROs, including protocol and report development or review, as well as timeline management
• Experience generating, integrating, reviewing, and interpreting toxicology data
• Experience authoring regulatory documents such as IBs, INDs, CTDs, and other health authority submissions
• Demonstrated ability to work effectively as an individual contributor in a matrixed environment, influencing without direct authority across scientific and functional teams
• Commitment to lifelong learning and professional development, including building or expanding subject matter expertise

PREFERRED:

• DABT certification, or a strong interest in obtaining DABT certification

Ionis offers an excellent benefits package! Follow this link for more details: Ionis Benefits

The pay scale for this position is $142,551 to $255,000

The pay scale for the Assistant Director position is $142,551 to $211,350
The pay scale for the Associate Director position is $172,501 to $255,000

NO PHONE CALLS PLEASE. PRINCIPALS ONLY.

Ionis Pharmaceuticals, Inc. and all its subsidiaries are proud to be EEO employers.

Equal Opportunity Employer
This employer is required to notify all applicants of their rights pursuant to federal employment laws.For further information, please review the Know Your Rights notice from the Department of Labor.