Onyx is now licensed to manufacture commercial API from our UK facility

Our testimonials

Our teams of chemists will guide your small molecule API through development and manufacturing from the moment a lead molecule is identified, taking it into Phase I studies and right through to commercial manufacture.

Good chemistry is at the core of everything we do.

Domain Therapeutics

Onyx Scientific has been a key partner throughout the preclinical development of our first clinical candidate, providing an efficient, reliable, solution-oriented service. A good connection between the synthetic, solid state and analytical teams made this CMC campaign a success. It was a real pleasure to work with them, and their flexibility was a big advantage for a biopharmaceutical company like ours. I recommend their expertise for putting in place a comprehensive package for scaling up from gram to kilogram quantities suitable for Phase I studies.

Anne-Laure – Project Leader

Cerebro CMC

“I have worked with Onyx for over 14 years on projects spanning the pre-clinical phase through to process validation. They continue to deliver pragmatic, cost effective solutions for my clients when faced with the inevitable technical challenges that they will encounter on these projects. Highly recommended and a great CDMO to work with.”

Ron Lawrence – Managing Partner


“Over the past years of collaboration, Onyx team have demonstrated their ability to take on challenging projects with a pragmatic approach. Their expertise and size allow them to be very agile and propose a good value fee for services. Their expansion towards commercial manufacturing offers great opportunities for niche products.”

Mathieu Louis – Director


This is the second company I’ve worked for where we’ve chosen Onyx Scientific as our CDMO partner, and I really value the strength of the long-term relationship. Onyx has always delivered high-quality API for IND-enabling toxicology studies and GMP API for clinical studies to a consistently high standard, on time, and in a cost-effective manner. The integration of chemistry development, salt screening and solid form development, GMP synthesis, and API manufacturing has really helped us move our programs forward with maximum efficiency. Onyx has always demonstrated a high degree of flexibility and responsiveness which we have found to be very important.”

Adele Rowley – Chief Scientific Officer

Skead Consulting Ltd

“I have worked with Onyx Scientific Team over a number of years on multiple projects. The integration of process development, solid state studies, analytical, non-GMP and GMP services works very effectively in rapidly supporting projects transitioning from research to early clinical development. The team at Onyx are very collaborative, flexible and responsive.”

Ben Skead – Managing Director

Epics Therapeutics

“We have collaborated with ONYX on several projects and continue to work with them as a trusted partner now. ONYX has had a critical, positive impact in the development of our synthetic pathways spanning from medicinal chemistry to large-scale GMP manufacturing, thorough process development of our synthetic and analytical chemistry culminating in successful achievement of GMP synthesis for multiple projects. We recommend ONYX as a preferred partner that stands out based on their expertise, communication, respect for deadlines, and solid state technology which complement their formidable integrated services platform.”

Guillaume Dutheuil – Head of Medicinal and Analytical Chemistry