Challenge

A medical device company developing a long-term, repeated-use implantable device encountered a challenge during biocompatibility testing when initial in vitro cytotoxicity results returned positive.
Given the device’s extended contact duration and clinical application, this raised potential regulatory concerns and jeopardized development timelines.

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Chemva’s Solution

Chemva conducted a detailed scientific review of all available biocompatibility data, including material composition, extractables and leachables (E/L) profiles, and comprehensive implantation study results.

While the cytotoxicity assay indicated a positive result, all other biological endpoints, particularly from subacute and subchronic implantation studies, demonstrated no local or systemic adverse tissue responses.

Recognizing the limitations of in vitro cytotoxicity testing, especially for certain material types and extraction conditions, Chemva applied a weight-of-evidence approach. We compiled a justification that highlighted the absence of inflammatory or necrotic effects in vivo, consistent tissue healing, and a lack of adverse findings in histopathology across multiple time points.

This integrated assessment was mapped clearly against ISO 10993-1 and ISO 10993-17 guidance, supporting a conclusion of biological safety.

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Impact Delivered

Chemva’s strategic data interpretation helped the partner avoid unnecessary re-testing and product reformulation. We successfully defended the device’s safety profile in a regulatory submission, allowing the program to stay on track. The reviewing agency accepted the justification without further inquiry, preserving both timeline and budget, ultimately helping the company proceed confidently to pivotal clinical trials.