Study question
Early clinical programs for dry-powder nasal sprays often face a practical question: can the device and formulation deliver a consistent dose, produce a defined spray, and keep most recovered material within the intended upper-airway size range? The sponsor had two anonymized dose variants and needed an in-vitro characterization package before moving the program forward.1
ARE Labs approached the work as product characterization, not an assessment of clinical efficacy. The sponsor needed data to respond to an FDA request for initial Phase 1 product characterization without disclosing proprietary product details. The report therefore had to connect the methods, measured performance, and interpretation while staying within the limits of the in-vitro data.1,2
The central questions were straightforward but technically important. Could each variant be actuated with consistent force? Did the emitted powder form a controlled spray pattern and plume? Was the delivered mass consistent? Did the aerodynamic particle size distribution show that most recovered material remained in the larger-particle nasal or upper-airway region rather than shifting into smaller respirable fractions?
Test package
The study combined mechanical actuation testing, NGI cascade impaction, HPLC recovery, spray pattern imaging, plume geometry capture, delivered dose assessment, and regional deposition classification. USP <601> and FDA nasal product guidance provide public context for the use of these product-quality measurements with inhalation and nasal drug products.1,2
ARE Labs evaluated both variants under controlled actuation to limit operator-related variability. Manual actuation can introduce noise, particularly when comparing dose variants or establishing a baseline for later development. The final data package linked the methods, measured performance, and interpretation within a GLP-aligned documentation framework.3
| Metric | Dose Variant A | Dose Variant B |
|---|---|---|
| Average actuation force | 5.68 +/- 0.54 kg | 5.44 +/- 0.25 kg |
| Delivered dose / emitted mass | 9.6 +/- 2.5 mg | 19.6 +/- 0.6 mg |
| Ovality ratio | 1.23 +/- 0.10 | 1.20 +/- 0.09 |
| Spray angle | 33.33 +/- 0.78 deg | 29.97 +/- 0.97 deg |
| Nasal / upper-airway deposition | 97.9% | 98.6% |
| Tracheobronchial deposition | 1.2% | 0.8% |
| Alveolar deposition | 0.8% | 0.6% |
| Exhalable fraction | 0.1% | 0.1% |
What the data showed
The two dose variants showed similar mechanical and spray-performance behavior. Average actuation force was 5.68 kg for Dose Variant A and 5.44 kg for Dose Variant B, with comparable variability. Most spray patterns were circular or slightly elliptical, and the measured spray angles remained within a narrow range.
Delivered dose or emitted mass scaled with the dose configuration: 9.6 mg for Dose Variant A and 19.6 mg for Dose Variant B in the summarized report data. The difference was expected from the configuration comparison. The development question was whether the broader performance profile remained interpretable across both variants.
Regional deposition result
The regional deposition profile was the most important technical result. Of the recovered material, 97.9 percent for Dose Variant A and 98.6 percent for Dose Variant B fell within the nasal or upper-airway category.
View figure data as a table
| variant | Nasal / upper airway |
|---|---|
| Dose Variant A | 97.9% |
| Dose Variant B | 98.6% |
Source: anonymized ARE Labs client study report and addendum.
- Percentages are calculated from recovered material in the anonymized study data table.
- The chart is not a clinical deposition claim.
The tracheobronchial, alveolar, and exhalable fractions were low for both configurations. Those values gave the sponsor a clear technical signal: under the tested conditions, the prototype behaved like a larger-particle nasal powder system rather than a primarily lung-directed aerosol.
View figure data as a table
| variant | Tracheobronchial | Alveolar | Exhalable |
|---|---|---|---|
| Dose Variant A | 1.2% | 0.8% | 0.1% |
| Dose Variant B | 0.8% | 0.6% | 0.1% |
Source: anonymized ARE Labs client study report and addendum.
- Excludes the nasal / upper-airway fraction (~98%) so the small fractions are legible.
- The chart is not a clinical deposition claim.
This was an in-vitro classification, not a clinical deposition claim. The source report did not calculate respirable MMAD or GSD because most recovered material was above the upper size range relevant to respirable curve fitting. In this case, the absence of those values was part of the technical interpretation, not simply a missing endpoint.
Regulatory-facing use
The client reported that the characterization report satisfied an FDA request for initial Phase 1 product characterization. This does not mean the product received approval, clearance, or agency endorsement.1
The package brought defined test methods, controlled actuation, quantitative recovery, clear interpretation, and documented limitations into one early-stage dataset. For teams preparing early clinical programs, this type of study can help address questions from regulators, investors, or internal program teams before the formulation or device design is locked.1,3
- Use this type of study when a program needs early performance characterization for an intranasal drug-device product.
- Keep interpretation limited to the data package; in-vitro regional classification is not a clinical deposition result.1
- Document limitations clearly when public FDA or USP context is used to explain the measurement rationale.1,2
A similar study design may be useful when a sponsor is preparing for first-in-human work, responding to an agency information request, comparing early device variants, evaluating a formulation change, or assembling data for internal program decisions. These endpoints need to be interpreted together because actuation, powder release, spray geometry, delivered dose, and aerodynamic sizing all contribute to the overall performance assessment.1
The study can also provide a baseline for later comparability work. If the actuator, powder formulation, filling process, or dose configuration changes, the same set of endpoints lets the sponsor compare new results with the original characterization package instead of treating each question as a separate method-development exercise.
Confidentiality also shaped the public case study. This version retains the dose variants, method categories, measured endpoint summaries, and regional deposition values. It omits the client name, product name, API, indication, client-specific codes, batch codes, personnel names, raw-data screenshots, and device-identifying details.
Summary
By bringing actuation, delivered dose, APSD, spray geometry, and regional deposition results into one package, the study gave the client an early performance baseline for two dry-powder nasal spray variants. It addressed the initial characterization need while keeping the conclusions within the limits of the study, without extending them into approval or clinical-effectiveness claims. For teams with a similar characterization need, ARE Labs may be a useful fit when several measurements must be brought together and the documentation and interpretation must remain closely aligned with the study question.