Principal Scientist/Associate Director, Medicinal Chemistry

Cambridge, MA
May 20, 2022
Required Education
Position Type
Full time

Theseus Pharmaceuticals is passionately committed to improving the lives of cancer patients by working to outsmart cancer resistance. Led by a team of targeted oncology pioneers with a proven track record developing and commercializing cancer therapeutics, we are developing the next generation of tyrosine kinase inhibitors (TKIs): “pan-variant” targeted therapies that address all known drug-resistant mutations. We believe a pan-variant approach is the only way to address cancer resistance. Our lead program, THE-630, is a pan-variant KIT inhibitor for patients with advanced gastrointestinal stromal tumors (GIST), whose cancer has developed resistance to earlier lines of kinase inhibitor therapy. We are also developing a fourth-generation, selective epidermal growth factor receptor (EGFR) inhibitor to address C797S-mediated resistance to first- or later-line osimertinib treatment in patients with non-small cell lung cancer (NSCLC).

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Role: Principal Scientist/Associate Director, Medicinal Chemistry


We are seeking a Principal Scientist/Associate Director, Medicinal Chemistry to join our passionate team of scientists. The ideal candidate should be a highly motivated, experienced and creative medicinal chemist with a proven track record of success in drug discovery from early Lead Generation through late-stage Lead Optimization. Candidates should be motivated to work in an intensely collaborative, multidisciplinary, team-based, and fast paced setting. This role will report to the Vice President of chemistry.

Who are we looking for?

  • You are ready to build the Chemistry function at Theseus and you are a person who thrives in a small company atmosphere!
  • You are an energetic and passionate pharmaceutical development professional who likes to think outside of the box, challenge the norm, and is passionate about the company's mission of discovering and developing new medications
  • You are a resourceful self-starter and team player with a strong results orientation
  • You consider yourself a guru in all the critical early-stage organization areas
  • You can develop trusting relationships to gain support and achieve results at all levels of the organization
  • A collegial individual who enjoys working in close collaboration with leaders in the research, development, manufacturing, quality, clinical and administrative areas of the company

What are we offering?

  • Membership within a growing, CARING and collegial organization
  • Being part of passionate, involved, and cutting-edge Team
  • Exposure to pioneering science and the discovery and the development of drugs to help treat patients with cancer

What we are looking for:

  • Lead an externalized medicinal chemistry team in the discovery of new development candidates to enrich Theseus’ oncology-focused pipelines
  • Manage outsourced chemistry resources, establishing and maintaining excellent working relationships with external providers. Creatively solve problems (synthetic routes, logistics etc.) to ensure delivery of compounds according to timelines.
  • Devise strategies to identify lead molecules and optimize them for potency, selectivity, and ADME properties using structure-based drug design approaches and multi-parameter SAR analysis
  • Work closely with computational chemistry, ADME, biology, pharmacology, and other key disciplines in a highly cross-functional environment
  • Ability to secure intellectual property while driving medicinal chemistry programs
  • Communicate project updates clearly and effectively to the broader team and key stakeholders

What you will bring:

  • A Ph.D./Postdoc in organic chemistry with 8 or more years of experience in Pharma/bio-tech drug discovery
  • Experience in leading projects and driving programs through the preclinical development process to candidate selection
  • Experience in managing outsourced resources with evidence of solving complex challenges
  • Expert in modern synthetic organic chemistry approaches and principles demonstrated through publications in peer-reviewed journals and patents
  • Experience working with computational chemists as part of project team in design of drug targets is required
  • Experience with kinase inhibitor design a plus
  • Strong interpersonal, communication, time management, and leadership skills

Our values:

Transparency: We work with honesty, openness, and integrity.

Community: We collaborate and thrive together.

Patient-Focused: We are committed to finding new medicines for patients.

Resolve: We never give up on our mission.

When You Join Theseus Pharmaceuticals You Will Have:

  • Location reachable by public transportation (Red Line)
  • Customized and competitive health coverage, including medical offered through BCBS (HMO/PPO), dental, and vision
  • Health Savings Account for medical expenses
  • Eligible from the first day for 401K with 100% match of the first 5%
  • A robust package of Theseus-paid insurance coverage, including life insurance, short-term and long-term disability
  • Unlimited time off and 11 Holidays
  • Winter Break: Theseus is closed for a Winter Break between Christmas and New Year

Location: Cambridge (Kendall Square), MA

Candidates should be aware that Theseus Pharmaceuticals requires all employees to be fully vaccinated against COVID-19. Newly hired employees must be vaccinated prior to their employment start date. Theseus is an equal opportunity employer and will provide reasonable accommodation to those unable to be vaccinated where it is not an undue hardship to the company to do so as provided under federal, state, and local law.

Theseus Pharmaceuticals is an equal employment opportunity employer and does not discriminate against any applicant because of race, creed, color, age, national origin, ancestry, religion, gender, sexual orientation, disability, genetic information, veteran status, military status, application for military service or any other class protected by state or federal law.

TO ALL AGENCIES: Please, no phone calls or emails to any employee of Theseus about our openings. All resumes submitted by search firms/employment agencies to any employee at Theseus via email, the internet or in any form and/or method will be deemed the sole property of Theseus unless such search firms/employment agencies were engaged by Theseus for this position and a valid agreement with Theseus is in place. In the event a candidate who was submitted outside of the Theseus agency engagement process is hired, no fee or payment of any kind will be paid.