Do You Need a Fractional Head of Preclinical?

Early-stage biotech companies face a recurring dilemma: you need senior nonclinical leadership to design IND-enabling programs, manage CRO relationships, and navigate regulatory strategy, but you may not have the budget, workload, or organizational maturity to justify a full-time VP-level hire. The fractional Head of Preclinical model has emerged as a practical solution for seed through Series A companies that need strategic expertise without committing to a permanent executive. This article explains what a fractional Head of Preclinical does, when you need one, and how to evaluate whether this model is right for your company.

What Does a Fractional Head of Preclinical Do?

A fractional Head of Preclinical serves as a part-time senior leader who takes ownership of your company's nonclinical development strategy. Unlike a consultant who delivers a report and moves on, a fractional leader is embedded in your team, participates in decision-making, and is accountable for outcomes over an extended engagement.

Core Responsibilities

• Nonclinical strategy design: Defining the complete nonclinical package required to support an IND filing, including pharmacology, ADME/PK, toxicology, biodistribution, and any modality-specific studies.
• CRO selection and oversight: Identifying, evaluating, and managing contract research organizations. This includes writing RFPs, reviewing protocols, monitoring study execution, and interpreting results.
• Regulatory interactions: Leading or supporting Pre-IND meeting preparation, drafting nonclinical sections of regulatory submissions, and responding to FDA information requests.
• Study design and protocol review: Ensuring that each study is designed to generate the data needed for regulatory submissions, with appropriate endpoints, species selection, and statistical approaches.
• Cross-functional coordination: Working with CMC, clinical, and regulatory teams to ensure the nonclinical program is integrated with the broader development plan.
• Board and investor communication: Presenting nonclinical strategy and progress to the board, and supporting fundraising efforts with clear articulation of the development plan.

What a Fractional Leader Is Not

A fractional Head of Preclinical is not a bench scientist, a CRO project manager, or a regulatory writer (though they may contribute to all of these). They are a strategic leader who brings the judgment and experience typically associated with a VP or SVP of Nonclinical Development at a larger company.

When Do You Need a Fractional Head of Preclinical?

Signs You Are Ready

• You have a development candidate and are planning IND-enabling studies. This is the most common trigger. Once you are designing GLP toxicology and other IND-enabling studies, you need senior nonclinical oversight.
• Your CRO is asking questions you cannot answer. If your CRO is driving study design decisions because nobody on your side has the expertise to lead, you have a leadership gap.
• You are preparing for a Pre-IND meeting. FDA interactions require someone who can design a defensible nonclinical strategy and articulate it clearly.
• Investors are asking about your nonclinical plan. Sophisticated biotech investors expect a clear, credible nonclinical development plan. If you cannot present one confidently, it affects your fundraising.
• You are spending more time managing nonclinical decisions than your core focus. If the CEO or Head of R&D is spending a disproportionate amount of time trying to manage nonclinical activities outside their expertise, it is time to bring in dedicated leadership.

Signs It May Be Too Early

• You are still in target validation or lead optimization with no clear development candidate.
• Your next milestone is entirely discovery-focused.
• You have no near-term plans for IND-enabling studies or regulatory interactions.

Fractional vs. Full-Time vs. CRO-Only

Understanding the trade-offs between these three approaches is essential for making the right decision.

Engagement Models

Fractional nonclinical leaders typically operate under one of two models, and sometimes a hybrid of both.

Retainer-Based Engagement

You retain the fractional leader for a set number of hours or days per month. This provides consistent availability and works well for ongoing programs where you need regular strategic input, CRO oversight, and participation in team meetings.

Best for: Companies in active IND-enabling phases with continuous decision-making needs.

Project-Based Engagement

The engagement is scoped around a specific deliverable or milestone, such as designing the nonclinical strategy, preparing for a Pre-IND meeting, or overseeing a critical GLP study.

Best for: Companies with a well-defined near-term need and a clear endpoint.

Hybrid Approach

Many engagements start project-based and transition to a retainer as the relationship develops and the company's needs expand. This allows both parties to establish fit before committing to an ongoing arrangement.

Scope of Responsibilities by Development Stage

The fractional Head of Preclinical's focus shifts as your company progresses through development.

Late Discovery / Lead Optimization

• Advise on translatability of preclinical models.
• Begin planning species selection and study design for IND-enabling work.
• Identify CROs with the right capabilities for your modality.

Pre-IND Planning

• Design the complete nonclinical IND-enabling package.
• Lead CRO selection and contracting.
• Prepare nonclinical content for the Pre-IND meeting briefing document.
• Draft key questions for FDA related to the nonclinical program.

IND-Enabling Studies

• Oversee GLP toxicology, biodistribution, and other IND-enabling studies.
• Review and approve protocols, interim data, and final study reports.
• Manage CRO relationships and address issues in real time.
• Coordinate with CMC on material supply for nonclinical studies.

IND Preparation and Submission

• Author or oversee nonclinical sections of the IND (Module 2.4 Nonclinical Overview, Module 2.6 Nonclinical Written and Tabulated Summaries, Module 4 Nonclinical Study Reports).
• Respond to FDA information requests related to nonclinical data.
• Support clinical hold responses if nonclinical issues arise.

Broader Fractional Leadership Roles

The fractional model extends beyond nonclinical development. Early-stage biotech companies increasingly use fractional executives across multiple functions:

• Fractional Head of Preclinical Development: Provides overall preclinical and translational leadership, integrating nonclinical, CMC, clinical, and regulatory functions into a cohesive development strategy.
• Fractional R&D Advisor: Offers senior scientific leadership, particularly for companies whose scientific strategy needs experienced oversight but whose stage does not yet warrant a full-time executive hire.
• Fractional BD Strategy Advisor: Supports partnering strategy, licensing discussions, and fundraising preparation. Particularly valuable for companies approaching Series A or exploring strategic partnerships.

These roles can be engaged individually or in combination, depending on where your company has the most significant leadership gaps.

How to Evaluate a Fractional Head of Preclinical

Not all fractional leaders are created equal. When evaluating candidates, consider the following:

Experience Criteria

• Modality expertise: Have they worked with your type of therapeutic (biologics, AAV gene therapy, RNA therapeutics)? Modality-specific experience matters enormously in nonclinical development.
• Regulatory track record: Have they successfully supported IND filings? Have they participated in Pre-IND meetings?
• CRO network: Do they have established relationships with CROs relevant to your program? This can accelerate timelines and improve study quality.
• Stage-appropriate experience: Have they worked with early-stage companies before? Someone who has spent their entire career at large pharma may struggle with the resource constraints and pace of a startup.

Working Style

• Communication: Are they responsive and clear? Fractional leaders need to be effective communicators because they are not in the office every day.
• Integration: Are they willing to participate in team meetings, attend board presentations, and function as a genuine member of your leadership team?
• Transparency: Do they proactively flag risks and challenges, or do they only report good news?

Making the Transition

If you start with a fractional leader and eventually grow to the point where a full-time hire makes sense, the transition should be planned thoughtfully:

• The fractional leader can help define the job description and evaluation criteria for the full-time role.
• There should be an overlap period where the fractional leader transfers institutional knowledge.
• In some cases, the fractional leader may transition into the full-time role themselves, if that is the right fit for both parties.