Solid Form Screening: Why It’s More Than Just a Box to Check—It’s a Strategic Decision

Solid Form Screening: Why It’s More Than Just a Box to Check—It’s a Strategic Decision

For many emerging biotechs, solid form screening feels like a routine task—something to complete and file away on the path to formulation. It’s often seen as a checkbox item: screen a few salts or polymorphs, pick one, move on.

But at DavosPharma, we’ve seen how underestimating this early step can lead to major downstream delays—some of them only surfacing during GMP manufacture or even clinical trials.

Done right, solid form screening is not just about finding a “workable” form. It’s about choosing the right form to unlock long-term success in stability, solubility, manufacturability, and regulatory acceptance.

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Why Solid Form Screening Matters

Every small molecule can potentially exist in multiple forms:

• Polymorphs (different crystal structures of the same molecule)
• Salts and co-crystals (to improve solubility or stability)
• Amorphous dispersions (for low-solubility compounds)

These forms may be chemically identical—but their physical behavior can vary dramatically. And that behavior impacts everything from drug product performance to regulatory classification.

A well-run solid form screening program answers questions like:

• Which forms are most stable under ICH conditions?
• Which forms are most bioavailable in GI fluids?
• Are any forms prone to form conversion during processing or storage?
• Is your chosen form patentable, or are you vulnerable to generic competition?

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What Happens When You Don’t Get It Right?

We’ve seen programs hit serious snags because this work was rushed or incomplete:

• Polymorphic conversion during formulation leads to batch failure or instability
• Low-solubility forms are selected for early tox, only to discover poor absorption in Phase 1
• Uncharacterized salts are flagged by FDA reviewers, requiring additional bridging or repeat studies
• Missed IP opportunities result in avoidable competition later

In short: choosing the wrong form—or failing to fully characterize it—can quietly derail development, often when it's most expensive to fix.

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Why Early-Stage Teams Skip This (And Why They Shouldn’t)

We get it: early programs are resource-constrained. When you’re managing tox studies, formulation, API scale-up, and funding timelines, solid form work can feel like a “Phase 2 problem.”

But here’s the truth: this is exactly when you should do it—before committing to a form for GLP tox, formulation development, or stability studies.

You don’t need to screen 100 forms. But you do need to understand the landscape, identify liabilities, and choose a form that gives you flexibility—not friction.

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How DavosPharma Approaches Solid Form Work

We don’t just pass you to a CRO and check the box. We:

• Design a screening strategy that balances scope and speed
• Coordinate vendors who specialize in crystallization, salt screening, and thermal analysis
• Interpret data in context—stability, formulation, exposure, and regulatory implications
• Guide decisions on whether to pursue polymorph, salt, or amorphous routes
• Map IP opportunities around your chosen form

This ensures the chosen form supports your clinical path, not just your next deliverable.

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Case in Point

A client working on an oral oncology agent approached us with a “final” API form—but it was prone to hydrate formation during storage. That change wasn’t obvious until 3-month stability data showed variability in assay and dissolution.

We helped them:

• Revisit polymorph screening
• Identify an anhydrous form with better long-term stability
• Justify a formulation change pre-IND that avoided a future clinical hold

One month of early work saved them six months of backtracking.

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Final Word: You’re Not Just Picking a Crystal—You’re Picking a Development Path

Solid form screening isn’t a formality. It’s a strategic decision point with implications for every aspect of your drug’s lifecycle: from stability and solubility to IP, CMC, and regulatory risk.

At DavosPharma, we help you make that decision with confidence—not just data. Because the right form doesn’t just fit today—it fits the future.

Let’s plan your screening strategy together. Contact us today to get started.