By: 2 August 2022
Orthox announces MHRA authorisation for clinical trial of knee cartilage repair FibroFix™ product platform

Key patent on implantable tissue repair devices granted in major economies

Orthox Limited, a clinical stage company developing medical implants to repair damaged knee articular cartilage and other orthopaedic injuries, announces it has received a Letter of No Objection from the UK’s MHRA, enabling the start of the company’s “FFLEX Study” (derived from the “FibroFix™ cartilage repair experience”). This study, supported by funding from  the National Institute for Health and Care Research (NIHR), Wellcome Trust and the European Innovation Council (EIC) Accelerator, will assess the safety and performance of Orthox’s FibroFix™ Cartilage P (FibroFix™) implant and accessory surgical instrumentation in the knee joints of patients suffering with cartilage injuries. Patient recruitment is expected to open in July at the lead clinical site, Southmead Hospital, North Bristol NHS Trust, UK before eventually being expanded across Europe.

The company also announces that it has received granted patents in the US, China, the UK, Germany, and France derived from key patent application number WO/2018/224800 (1) titled “Implantable Tissue Repair Devices And Methods For Manufacturing The Same”. The patent family, which also includes an Australian patent granted in 2021, offers protection for the unique self-anchoring capability of Orthox’s FibroFix™ Cartilage implant enabling stable implantation and fixation to the underlying bone.

Commenting on the approval, and patent grant, Nick Skaer, co-founder, and CEO of Orthox said: “This MHRA approval is another significant milestone for our award winning FibroFix product platform. FibroFix is unique in emulating the functional properties of cartilage while also, in laboratory tests, facilitating rapid tissue regeneration. It could make a real difference to patients suffering the debilitating effects of serious knee cartilage injuries. With our approach there is significant bone sparing and strong tissue integration of the implant, which will result in much faster patient recovery from surgery. The multiple grants of our patent in key global economic territories further validates the novelty of our technology and extends our intellectual property coverage across countries in which a significant number of patients could be treated with our FibroFix implants every year.”

The Study Chief Investigator, Michael Whitehouse, Professor of Trauma & Orthopaedics at the University of Bristol and NIHR Bristol Biomedical Research Centre (Bristol BRC), commented: “This technology represents the culmination of a huge amount of development of the implant and the associated instruments to allow a reliable and reproducible operation. It potentially fills a gap in current available treatments. It would allow the treatment of immediate pain and limited function for patients with focal cartilage problems. Typically, operations for these problems are technique dependent or require prolonged periods of limited weightbearing or restricted activity. The instruments developed for this implant and the implant itself provide very strong fixation during the course of the operation and allow an early return to normal activity. Successful treatment of focal cartilage lesions may help to reduce the risk of more widespread joint damage in the future.”

FibroFix™ is targeted at treating injuries to the articular cartilage in the knee which covers the ends of the femur (thigh bone) and tibia (shin bone). It protects the surface of these bones and allows the joint to operate smoothly. Around 900,000 patients a year in the US suffer from traumatic, often sports-related, injuries to articular cartilage in the knee [2]. These injuries are inadequately served by current procedures, typically debridement (trimming away the damaged tissue), and/or microfracture (punching holes in the subchondral bone, to allow bleeding and formation of scar and fibrous tissue). Knee cartilage damage can lead to osteoarthritis, which resulted in over 1.3 million total knee replacements in the US and EU in 2011 [3,4].



(1) – WO2018/224800

(2) – Cartilage Defects: Incidence, Diagnosis, and Natural History. Oper. Tech. Sports Med. 26, 156–161 (2018):

(3) – International Orthopaedics (SICOT) (2011) 35:1783–1789 Kurtz et al.:

(4) – Agency for Healthcare Research and Quality, in the U.S., over 754,000 knee replacements were performed in 2017: