US-based pharmaceutical company Eli Lilly and Company (Lilly) has received the US Food and Drug Administration (FDA) approval for Jaypirca (pirtobrutinib), under its accelerated approval pathway.

Jaypirca (pirtobrutinib), previously known as LOXO-305, is a highly selective non-covalent inhibitor of the enzyme BTK, which is found across B-cell leukaemias and lymphomas.

The drug is indicated for adults with a type of chronic lymphocytic leukaemia or small lymphocytic lymphoma (CLL/SLL), who have received at least two prior lines of therapy.

It is approved as an oral prescription medicine, 100mg or 50mg tablets taken as a once-daily 200 mg dose with or without food until disease progression or unacceptable toxicity.

Jaypirca may also receive continued approval for this indication, subject to verification and description of clinical benefit in a confirmatory trial.

Furthermore, Jaypirca comes with a labelled warning for infections, haemorrhage, cytopenias, cardiac arrhythmias, second primary malignancies, and embryo-foetal toxicity.

The University of Texas MD Anderson Cancer Centre Department of Leukaemia medical director and CLL section head William Wierda said: “Once patients with CLL or SLL have progressed on covalent BTK inhibitor and BCL-2 inhibitor therapies, treatments are limited and outcomes can be poor, making the approval of Jaypirca a meaningful advance and much-needed new treatment option for these patients.

“Jaypirca offers a new treatment option and different approach to targeting BTK, providing clinical benefit for a high proportion of patients with CLL or SLL in the BRUIN Phase 1/2 trial whose disease progressed following treatment with a covalent BTK inhibitor and with a BCL-2 inhibitor.”

The US FDA approval of Jaypirca is based on positive data from a subset of patients in the BRUIN, an open-label, single-arm, multicohort, international, Phase ½ clinical trial.

In the Phase 1/2 trial, 108 patients with CLL/SLL, previously treated with at least two prior lines of therapy, including a BTK inhibitor and a BCL-2 inhibitor, were given Jaypirca.

Jaypirca 200 mg was given once daily and was continued until disease progression or unacceptable toxicity.

The most common prior lines of therapy the study participants received were ibrutinib (97%), acalabrutinib (9%) and zanubrutinib (0.9%).

In the phase ½ study, Jaypirca established efficacy based on overall response rate (ORR) and duration of response (DOR), as evaluated by an independent review committee (IRC).

In the pooled safety population, the most common adverse reactions (ARs) to Jaypirca include decreased neutrophil count, haemoglobin, lymphocyte count, and platelet count, along with musculoskeletal pain, fatigue, diarrhoea, Covid-19, bruising, and cough.

Loxo@Lilly CEO Jacob Van Naarden said: “This FDA approval, the second for Jaypirca in 2023, underscores the impactful clinical benefit of continuing to leverage the BTK pathway with Jaypirca for patients with CLL or SLL as seen in the BRUIN trial.

“These first two indications for Jaypirca represent the beginning of the eventual impact that we hope Jaypirca can have for patients, and we look forward to seeing the results of the comprehensive Phase 3 development program across CLL, SLL and MCL.”