RXC005 (Jaypirca^TM (pirtobrutinib)) Reversible BTK inhibitor

The Bruton’s tyrosine kinase (BTK) inhibitor programme was sold to Loxo Oncology (now part of Eli Lilly) in July 2017 for $40 million, and pirtobrutinib (originally RXC005, then LOXO-305, now Jaypirca^TM) was approved in January 2023 under the FDA’s Accelerated Approval pathway for the treatment of adult patients with relapsed or refractory mantle cell lymphoma (MCL) after at least two lines of systemic therapy, including a Bruton’s tyrosine kinase (BTK) inhibitor. In December 2023, Jaypirca received further approval for the treatment of adult patients with Chronic Lymphocytic Leukemia (CLL) or Small Lymphocytic Lymphoma (SLL) who have received at least two lines of therapy, including a BTK inhibitor and a BCL-2 inhibitor. Whilst Redx is not due to receive any future payments in relation to RXC005, the scientific story underlines our track record for discovery and delivery of valuable molecules that can succeed in the clinic, resulting from our rigorous target selection and world class scientific delivery.

RXC005 was successfully nominated as a drug candidate in October 2016 and the preclinical data supporting this decision were presented at the 58th American Society of Hematology (ASH) in December 2016 (Guisot et al., 2016) and the XVII International Workshop on Chronic Lymphocytic Leukemia (iwCLL) in May 2017 (Guisot et al., 2017).

In March 2025, The Royal Society of Chemistry’s Biological and Medicinal Sector awarded Dr Nicolas Guisot, VP & Head of Development Science at Redx, the Malcolm J. Campbell Memorial Prize for pioneering the development of reversible BTK inhibitors.

Jaypirca^TM is a trademark owned by or licensed to Eli Lilly and Company, its subsidiaries, or affiliates.