MSL - West

definiumtherapeutics

Remote

Posted Jul 20, 2026

Other
27 - Medical Affairs

Job description

Definium Therapeutics is a late-stage clinical biopharmaceutical company and our mission is to forge a new era of psychiatry by applying scientific rigor to psychedelics, with the goal of developing accessible treatments that unlock healing at scale.

Our lead product candidate, lysergide tartrate (our proprietary orally disintegrating tablet form of lysergide (LSD) D-tartrate), represents a highly differentiated, potential best-in-class opportunity for patients suffering from generalized anxiety, major depressive disorder, and posttraumatic stress disorder. Our early stage pipeline includes DT402, the R-enantiomer of MDMA and is under development to target the core symptoms of autism spectrum disorder (ASD), specifically addressing social communication challenges.

Guided by the recognition that patients deserve more than better, Definium is relentlessly advancing a new generation of therapeutics intended to address the underlying causes of psychiatric and neurological disorders. By turning evidence into impact, Definium aims to change the trajectory of today’s mental health care crisis and enable a healthier future. Headquartered in New York, Definium Therapeutics trades on Nasdaq under the symbol DFTX.

Together we are moving psychiatry forward—beyond better, into a boundless future. Join us!

The Medical Science Liaison (MSL) will serve as a field-based scientific and clinical expert supporting our psychiatry portfolio, building and maintaining strong relationships with Key Opinion Leaders (KOLs), healthcare providers, policy influencers, and other stakeholders. This role will focus on engaging the medical community to communicate scientific data, gather clinical insights, and support alignment between our research and development efforts and real-world practice needs.

The ideal candidate will have a strong foundation in psychiatric disorders, a passion for science-driven conversations, and the ability to operate effectively in a small, fast-growing biotech environment.

Responsibilities:

Identify, develop, and maintain professional relationships with KOLs, clinical investigators, and key stakeholders across academic and clinical psychiatry
Serve as a scientific resource in the field, delivering accurate, balanced, and compliant scientific information to facilitate high-quality scientific exchange
Support scientific education at national and regional psychiatry conferences, advisory boards, and educational events
Gather and communicate field insights to internal stakeholders to inform strategy and decision-making
Assist in maintaining best practices for field insight capture, documentation, and KOL engagement
Respond to unsolicited requests for medical information from healthcare professionals in accordance with company policies
Monitor and report on competitor landscape and emerging clinical data
Support clinical teams with trial site identification and enrollment initiatives as needed
Support investigator-initiated trial (IIT) and Phase IV activities as appropriate
Collaborate with Government Affairs and HEOR to provide scientific and clinical expertise in support of policy discussions and stakeholder briefings
Represent the company, as requested, at regional mental health or policy-related events
Ensure all interactions are conducted in accordance with company policies, regulatory guidelines, and compliance requirements

Qualifications:

Advanced scientific degree (PharmD, PhD, MD, DNP, or equivalent) strongly preferred
Minimum of 2–5 years of MSL or related medical affairs experience; psychiatry/CNS experience preferred
Strong understanding of psychiatric disease states and treatment paradigms
Demonstrated ability to engage in scientific dialogue with healthcare professionals
Strong presentation, communication, and interpersonal skills
Ability to interpret and present complex scientific data clearly and concisely
Familiarity with CRM systems, insight tools, and compliant field operations
Comfortable working in a high-growth, fast-paced biotech environment with cross-functional collaboration
Willingness to travel up to 60% as needed

The starting base pay range for this position is $175,000.00 - $230,000.00. Compensation will be determined based on several factors including, but not limited to, skill set, years of experience, and the employee’s geographic location.

Employees in this role may be entitled to additional compensation, including bonus and equity. Benefits information is listed on our Jobs Page. The Company provides competitive benefits to employees including:

100% paid health benefits including Medical, Dental and Vision for you and your dependents
401(k) program with company match and vesting after the turn of the first month after your start date
Flexible time off
Generous parental leave and some fun fringe perks!