Long-term Responders to Nanoparticle Albumin-bound Paclitaxel Following Immune Checkpoint Inhibitor in Non-small Cell Lung Cancer.

BACKGROUND/AIM: The efficacy of cytotoxic chemo-therapy has been reported to improve after immune checkpoint inhibitor (ICI) administration. We previously conducted a multicenter prospective clinical study to evaluate the efficacy and safety of nanoparticle albumin-bound paclitaxel (nab-PTX) after ICI treatment. In that study, some patients showed a long-term response to nab-PTX, which is not usually observed with single-agent chemotherapy. The present study aimed to evaluate the clinical characteristics of these patients.

PATIENTS AND METHODS

We retrospectively analyzed updated data from 29 patients enrolled in our clinical study who received nab-PTX monotherapy after ICI treatment. We defined a "long-term responder" as a patient who achieved a 1-year progression-free survival (PFS).

RESULTS

Among the 29 patients, 10 (34.5%) were long-term responders, two of whom achieved a 5-year PFS. A key difference between long-term and non-long-term responders was that the long-term responders had a significantly higher number of patients with Eastern Cooperative Oncology Group-performance status of 0 (70.0% versus 10.5%; p=0.002). Furthermore, median cycles of previous ICIs and median treatment cycles were significantly higher in long-term responders than in non-long-term responders (8 cycles versus 3 cycles; p=0.03) (5.9 months versus 2.0 months; p=0.02). In the 10 long-term responders, six patients required at least a one-stage dose reduction owing to adverse events, and four patients required a two-stage dose reduction.

CONCLUSION

Nab-PTX administration after ICI treatment may elicit a long-term response. A long-term response can be achieved even with a dose reduction due to adverse events.