Before committing to a full injectable or ophthalmic formulation development program, most early-stage companies benefit from a focused feasibility study: a compact scope of work designed to answer the critical questions about your compound before you’ve invested in a complete formulation development program.
At Callan, we routinely run feasibility studies on small molecules and peptide drug substances. The core formulation development work, which includes analytical method implementation and development, formulation screening, and initial characterization, can be completed in four to eight weeks.
Here’s what the work looks like in practice.
Kevin Sill, PhD
President & Co-Founder
Callan Pharma Services
The Target Formulation Profile
A formulation feasibility study at Callan is built around the Target Formulation Profile (TFP). Route of administration, drug product presentation, required drug substance concentration, storage conditions, pH, viscosity – all these parameters must first be defined. Once these boundaries are set, Callan can begin the process of devising a formulation screening strategy.
Here’s an example TFP:
| Attribute | Ideal | Acceptable |
|---|---|---|
| API concentration | 10 mg/mL | 5-9 mg/mL |
| Dosage Form | Liquid or emulsion | Lyophilized powder |
| Viscosity | < 2 cP | 2–3 cP |
| pH | 7.0 | 5.5-6.5 |
| Osmolarity | Isotonic (280–300 mOsm/kg) | Slightly hypotonic (240–270 mOsm/kg) |
| Reconstitution stability (lyophilized) | > 24 hrs | 3-23 hrs |
| Excipients | At or below IID levels | Above IID levels |
| Route of Administration | Subcutaneous (preferred) | Intravenous (fallback) |
| Stable Storage Conditions | Controlled room temperature (20–25°C) | Frozen (–20°C) |
What the Work Involves
Analytical method implementation or development. All work at Callan starts by either implementing a client’s existing HPLC assay or developing a suitable research-grade method. This allows us to assay the drug substance in the formulations and track changes in concentration or purity throughout both the formulation screening and subsequent pilot stability studies.
Formulation screening. We prepare and characterize a panel of candidate formulations governed by the target formulation profile. Each candidate is evaluated for key physicochemical attributes including appearance, pH, osmolarity, concentration, and initial stability indicators.
Pilot stability assessment. At Callan, we strongly encourage clients to get early formulation candidates on stability as soon as possible. Viable formulations identified during the screening phase are placed on accelerated and refrigerated stability to generate directional data. Plan for an additional eight to twelve weeks from the point formulations are placed on stability to receipt of meaningful data.
IP landscape review. Both Callan founders are registered USPTO patent agents and can assess the formulation IP landscape as part of the feasibility engagement. This includes white space analysis and identification of potentially defensible formulation approaches. For clients who have already completed their own IP work, this component can be scoped out entirely.
Summary report. At the end of every feasibility study, you receive a summary of findings and recommendations: what was done, what the data showed, which formulation approach we recommend advancing, and why. The report is structured to be actionable for your internal team and your development partners as you plan next steps.
Is a Feasibility Study Right for Your Program?
A formulation feasibility study makes the most sense if you have one or several drug substance candidates that have demonstrated promising in vitro or in vivo data, but presently not in a viable drug product presentation. Callan can help provide quick answers and data to support the feasibility of advancing each of your drug substance candidates.
If you already have a formulation but are heading toward a CDMO handoff, a targeted feasibility scope focused on process robustness and scalability can surface problems before your CDMO encounters them.
If you’re not sure which situation applies to you, reach out for an introductory call. We’ll ask a few questions about your compound and development stage and give you a direct answer about whether a feasibility study is the right next step.
FAQ: Formulation Feasibility Studies
What is a formulation feasibility study?
A formulation feasibility study is a focused, time-limited scope of research work designed to answer the critical questions about your compound’s formability before you commit to a full development program. At Callan, a feasibility study typically includes analytical method development or implementation, formulation screening against a defined target formulation profile, pilot stress testing, and short-term stability assessment. The goal is to identify a viable lead formulation approach and map the remaining development risks before you’ve invested in a complete CMC program.
How long does a formulation feasibility study take?
The core work, which includes analytical method development or implementation, formulation screening, and initial characterization, typically completes in four to eight weeks. Pilot stability data requires additional time. Stability studies run on a fixed schedule and cannot be compressed; plan for an additional eight to twelve weeks from the point lead formulations are placed on stability to receipt of meaningful directional data.
What is a Target Formulation Profile and why does it matter?
A Target Formulation Profile (TFP) is a defined set of attributes that your drug product needs to meet, organized into ideal and acceptable ranges. It captures parameters such as API concentration, dosage form, pH, osmolarity, viscosity, storage conditions, and route of administration. At Callan, the TFP is the foundation of every feasibility study. Without defined boundaries, formulation screening has no objective standard to screen against. Establishing the TFP before work begins ensures that the formulations we evaluate are relevant to your actual clinical and commercial goals, not just technically interesting.
When does a formulation feasibility study make sense for my program?
A feasibility study makes the most sense when you have one or more drug substance candidates with promising in vitro or in vivo data but are not yet clear what a formulated drug product would look like. It is also valuable when you are heading toward a CDMO handoff and want to identify potential process robustness or scalability issues before your CDMO encounters them.
