1369P - Trilaciclib combined with intraventricular injection chemotherapy in the treatment of advanced NSCLC with leptomeningeal metastasis: A prospective, single-arm, phase II clinical trial

Background

Intraventricular injection chemotherapy of pemetrexed is found to be effective in the treatment of non-small cell lung cancer (NSCLC) patients with leptomeningeal metastasis(LM),but chemotherapy-induced myelosuppression (CIM) greatly affects the quality of life and survival of patients. Trilaciclib has been approved for the use of SCLC before chemotherapy to reduce the incidence of CIM. This study aimed to evaluate the myeloprotective effect and safety of trilaciclib combined with intraventricular injection chemotherapy in the treatment of advanced NSCLC with LM.

Methods

This was a prospective, single-arm,phase Ⅱ clinical study (NCT 06332287). All patients underwent stereotactic installation of an Ommaya reservoir. IVC via the Ommaya reservoir was started the day after surgery. Patients received 30 mg pemetrexed and 240 mg/m² trilaciclib twice weekly for 2 weeks as consolidation therapy, and then repeated every 3 to 4 weeks until disease progression or unacceptable toxicity, or patient refusal occurred.The primary endpoint was the incidence of severe neutropenia (SN) in the first cycle. The secondary endpoints were myeloprotective effect and safety of trilaciclib.

Results

All 28 enrolled NSCLC patients received trilaciclib before chemotherapy by December 2023. There were 13 males and 15 females patients, with a median age of 58 years (range:32-72). 96.4% patients received at least 2 lines of prior treatment. Nine patients received 4 cycles of trilaciclib combined with chemotherapy, with a median of 2 cycles (range:1-4). None of the 28 patients developed SN or febrile neutropenia (FN) in the first cycle. During treatment, only 1 patient (4%) developed grade 3/4 neutropenia, and no grade 3/4 anemia and ≥ grade 3 thrombocytopenia were observed. No dose reduction of chemotherapy drugs was observed. In terms of safety, most common adverse events were grade 1/2, and no treatment-related deaths occurred.

Conclusions

Trilaciclib yielded good myeloprotective effect and safety in advanced NSCLC with leptomeningeal metastasis who received intraventricular injection chemotherapy.

Clinical trial identification

NCT 06332287.

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.