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Why specialized CDMO expertise matters for patches and oral films

Written by Roxane Viguier | Jun 16, 2026 7:43:28 AM

Patient-centric drug delivery systems are gaining increasing attention across the pharmaceutical industry. Patches and oral films offer innovative alternatives to conventional dosage forms by improving ease of administration, treatment adherence, and patient comfort.

From pediatric and geriatric applications to CNS therapies, hormone delivery, smoking cessation, these advanced dosage forms are becoming increasingly attractive for pharmaceutical and biotechnology companies seeking differentiated products.

Pharmaceutical companies can rely on different outsourcing models depending on their development needs, from CROs (Contract Research Organization), and CMOs (Contract Manufacturing Organization) to fully integrated CDMOs (Contract Development and Manufacturing Organization). In our previous article, Differences between CDMO, CDO, CMO and CRO: which partner should you choose for your project?, we explored the respective roles of these partners throughout the drug development process.

However, for highly specialized dosage forms such as patches and oral films, technical expertise itself often becomes a key success factor.

Developing patches and oral films is far more complex than manufacturing traditional tablets or capsules. Their success depends on a combination of formulation expertise, manufacturing precision, analytical capabilities, and regulatory understanding.

This is why working with a specialized CDMO can play a critical role in the success of a project as well as on cost and time.

 

Oral films and patches are highly specialized dosage forms

Unlike conventional solid oral dosage forms, patches and oral films are thin-layer systems that combine pharmaceutical science, material science, process engineering, and patient-centric design.

Their performance depends not only on the active pharmaceutical ingredient (API), but also on multiple critical parameters such as:

  • Film or patch thickness and uniformity
  • Mechanical resistance and flexibility
  • Mucoadhesion or adhesion performance
  • Drug release and permeation properties
  • Manufacturing process
  • Residual solvent levels
  • Packaging compatibility
  • Long-term stability

Even minor process variations can significantly impact product quality, drug release, adhesion behavior, or patient acceptability.

For oral films, manufacturers must ensure homogeneous API distribution while maintaining the required flexibility, disintegration profile, or mucoadhesive properties.

For patches, challenges become even more complex due to the skin’s natural barrier function. Achieving controlled and reproducible drug delivery through the skin requires careful optimization of the formulation, adhesive system, and permeation profile.

These technical constraints explain why patches and oral films require dedicated development and manufacturing expertise.

 

Formulation challenges require specialized expertise

Oral films: balancing performance, stability and patient acceptability

Oral films offer many advantages for patients, including easy administration, precise dosing, and improved compliance, particularly for pediatric and geriatric populations.

However, developing a robust oral film formulation involves several technical challenges.

One of the most critical parameters is content uniformity. Because films are extremely thin and often contain low-dose APIs, achieving homogeneous distribution of active ingredients across the entire surface is essential.

Taste masking also remains a key challenge for orally administered films. Poor palatability can negatively impact patient adherence, especially in sensitive patient populations.

Mechanical properties must also be carefully optimized. Films must remain flexible enough to avoid brittleness while maintaining sufficient tensile strength for handling, packaging, and administration.

Oral film development requires careful control of several critical attributes, including rapid disintegration for orodispersible films, mucoadhesion for transmucosal delivery systems, moisture sensitivity, and API compatibility with excipients and solvents.

At AdhexPharma, dedicated oral film development platforms support the optimization of disintegration, mucoadhesion, mechanical performance, and patient acceptability across a wide range of applications.

Learn more about: Oral films

Patches: controlling drug delivery into and through the skin

Transdermal and topical patches present another level of formulation complexity.

The skin is an effective natural barrier designed to protect the body from external substances. Delivering an API through this barrier in a controlled and reproducible manner requires advanced formulation expertise and precise control of permeation parameters.

Developers must optimize multiple parameters simultaneously, including:

  • Adhesion performance throughout wear time
  • Drug permeation kinetics
  • API solubility and stability
  • Residual solvent content
  • Crystallization risks during storage
  • Compatibility between API(s), excipients, release liners, and packaging materials

The balance between adhesion and patient comfort is particularly critical. Patches must adhere reliably during application while remaining comfortable and easy to remove.

Advanced patch systems such as matrix patches also require precise control of the diffusion area and drug release profile.

AdhexPharma supports the development of advanced topical and transdermal systems designed to ensure controlled drug delivery, reliable adhesion performance, and consistent product quality.

Learn more about: Patches

 

Scale-up and manufacturing challenges are often underestimated

Many formulations demonstrate promising performance during early laboratory development but encounter significant challenges during industrialization.

Scale-up is often one of the most critical phases in oral film and patch development.

The transition from laboratory batches to pilot or commercial manufacturing can impact:

  • Coating consistency
  • Drying efficiency
  • Solvent evaporation
  • Film thickness uniformity
  • Lamination quality
  • Batch reproducibility

For planar dosage forms, manufacturing precision is essential.

Coating and drying precision

The coating and drying process directly influences product performance.

During manufacturing, the formulation mixture is coated onto a liner to create a smooth and uniform film before passing through several drying zones.

Even small variations in:

  • Coating thickness
  • Drying temperature
  • Web speed
  • Solvent evaporation

can affect mechanical properties, adhesion behavior, drug load, or residual solvent levels.

Roll-to-roll manufacturing expertise

Industrial production of oral films and patches requires specialized roll-to-roll manufacturing capabilities.

Processes such as:

  • Slitting
  • Lamination
  • Converting
  • Primary packaging

must all be carefully controlled to maintain product consistency and quality.

At AdhexPharma, manufacturing operations are supported by continuously controlled production lines designed for flexible production from small clinical batches to commercial-scale manufacturing.

Technology transfer and GMP manufacturing

Technology transfer can also become a major challenge when development and manufacturing are handled by different partners.

Misalignment between formulation development, analytical methods, and industrial equipment may lead to delays, additional development work, or reproducibility issues.

An integrated CDMO approach helps reduce these risks by ensuring continuity between:

  • Formulation development
  • Process optimization
  • Analytical testing
  • Clinical trial supply manufacturing
  • Commercial GMP production

This integrated workflow can significantly facilitate scale-up and accelerate product development timelines.

 

Analytical and regulatory expectations are increasingly demanding

Oral films and transdermal patches require highly specialized analytical characterization throughout development and commercialization.

In addition to standard pharmaceutical testing, planar dosage forms often require dedicated analytical methods adapted to their specific properties.

Specialized analytical capabilities

Analytical programs may include:

  • Assay and purity testing
  • Drug release studies
  • Residual solvent determination
  • Adhesion characterization
  • Water content analysis
  • Tensile testing and flexibility studies
  • Permeation studies using human skin or mucosal models

In vitro permeation testing can play a critical role during feasibility and formulation optimization stages, particularly for transdermal and transmucosal products.

At AdhexPharma, analytical services support all stages of development, from analytical method development and validation to release testing and stability studies.

Stability and packaging considerations

Stability is another critical aspect of oral film and patch development.

Because these dosage forms are often sensitive to:

ICH stability studies and packaging assessments are essential to ensure long-term product integrity and performance.

Regulatory expectations

Regulatory agencies such as the FDA and EMA also maintain high expectations for these advanced dosage forms. In our previous article, Overview of FDA guidelines for transdermal patches in the US with AdhexPharma, your CDMO partner, we explored some of the key regulatory considerations specific to transdermal systems in the US market.

Depending on the product type, developers may need to address:

  • IVRT or IVPT studies
  • Adhesive characterization
  • Extractables and leachables
  • GMP compliance
  • Validation of specialized analytical methods

Working with a CDMO experienced in these regulatory expectations can help pharmaceutical companies anticipate challenges earlier and streamline product development.

 

Why specialized CDMO expertise makes a difference

Because oral films and transdermal patches combine formulation complexity, specialized manufacturing, analytical requirements and regulatory constraints, partnering with an experienced CDMO can provide significant advantages throughout the project lifecycle.

A specialized CDMO can support pharmaceutical and biotechnology companies from early feasibility assessment to commercial manufacturing.

Integrated development and manufacturing

Integrated teams facilitate communication between formulation scientists, analytical experts, process engineers, and manufacturing specialists.

This approach helps:

  • Reduce technology transfer risks
  • Improve process robustness
  • Accelerate troubleshooting
  • Facilitate industrial scale-up
  • Ensure continuity between development and GMP production

Specialized infrastructure and expertise

Dedicated equipment and infrastructure are also essential for these dosage forms.

At AdhexPharma, manufacturing capabilities include:

  • Early-stage R&D capabilities with batch sizes below 5 kg
  • Mixing capacities from 5 to 300 kg for development and commercial manufacturing
  • Multiple continuously controlled coating lines
  • Flexible packaging configurations
  • GMP-compliant manufacturing environments
  • Handling of highly potent APIs, hormones and narcotics

Combined with over 40 years of experience in oral film and transdermal patch development, these capabilities support projects from early-stage feasibility to worldwide commercial manufacturing.

Supporting innovation in patient-centric drug delivery

As patient-centric dosage forms continue to evolve, pharmaceutical companies increasingly require partners capable of combining scientific expertise with industrial reliability.

Specialized oral film and transdermal patch technologies can help improve patient adherence, optimize drug delivery, and differentiate pharmaceutical products in competitive markets.

By combining formulation expertise, analytical capabilities, industrial manufacturing and regulatory support, specialized CDMOs can help transform innovative concepts into robust commercial products.

 

Conclusion

Oral films and transdermal patches offer major opportunities for modern drug delivery, but their successful development requires far more than conventional pharmaceutical manufacturing capabilities.

These advanced dosage forms involve complex formulation challenges, specialized industrial processes, demanding analytical characterization, and strict regulatory expectations.

For pharmaceutical and biotechnology companies, working with a specialized CDMO can help reduce technical risks, facilitate scale-up, accelerate development timelines, and support successful product commercialization.

With dedicated expertise in complex dosage forms, state-of-the-art manufacturing and analytical capabilities, and fully integrated GMP development services, AdhexPharma supports partners from idea to market through solutions designed around patient needs.