Virtual Library

Start Your Search

Sachi Okawa



Author of

  • +

    P2.04 - Immuno-oncology (ID 167)

    • Event: WCLC 2019
    • Type: Poster Viewing in the Exhibit Hall
    • Track: Immuno-oncology
    • Presentations: 1
    • Moderators:
    • Coordinates: 9/09/2019, 10:15 - 18:15, Exhibit Hall
    • +

      P2.04-72 - Clinical Feature and Management of Acquired Resistance to PD-1 Inhibitor in Advanced NSCLC (ID 1343)

      10:15 - 18:15  |  Presenting Author(s): Sachi Okawa

      • Abstract
      • Slides

      Background

      Programmed cell death-1(PD-1) inhibitors have emerged as a standard treatment for patients with advanced non-small cell lung cancer (NSCLC). However, the patterns of disease progression (PD) after an initial response (acquired resistance) to a PD-1 inhibitor and the efficacy of continuous PD-1 inhibitor therapy beyond PD remain unclear.

      Method

      We retrospectively reviewed medical charts of advanced NSCLC patients treated with nivolumab or pembrolizumab as any line treatment at National Cancer Center Hospital East between January 2016 and October 2017. Acquired resistance was defined as disease progression after 6 months or more of treatment with a PD-1 inhibitor. Isolated disease progression was defined as progression in 1 site or organ, whereas systemic progression involved >1 site or organ. The clinical feature, PD pattern of acquired resistance, subsequent treatment and survival after acquired resistance were investigated.

      Result

      Fifty-nine patients were treated with a PD-1 inhibitor for 6 months or more, of whom 27 patients (46%) had acquired resistance. Only 1 patient received a PD-1 inhibitor as fist-line treatment. Twelve patients were diagnosed as adenocarcinoma, 4 as squamous-cell carcinoma and 11 as NSCLC-NOS. The response at 6 months of treatment was partial response in 17 patients (63%) and stable disease in 10 patients (37%). The median time to acquired resistance was 12.2 (95%CI 9.3-17.8) months. Progression in the lesion identified at baseline was observed in 16 patients (59%), new lesions appeared in 4 patients (15%) and both of them occurred in 7 patients (26%). Overall, the most frequent progression site was lung (n=14, 52%), followed by thoracic lymph node (n=7, 26%), pleura (n=6, 22%) and brain (n=4, 15%). The median number of progressed lesions was 2 and 67% of patients had progression limited to one (30%) or two (37%) lesions. Ten patients (37%) had isolated disease progression in lung (n=3), brain (n=3), thoracic lymph node (n=2), neck lymph node (n=1) and adrenal (n=1). In 11 patients, PD-1 inhibitor therapy was continued beyond PD with (n=4) or without local radiotherapy (n=7). The median OS after acquired resistance in patients with or without continuous PD-1 inhibitor therapy beyond PD was 9.9 months and 10.7 months, respectively.

      Conclusion

      Our results suggest that the most common pattern of acquired resistance to a PD-1 inhibitor was progression of thoracic lesion identified at baseline. One-third of the patients had isolated disease progression. The efficacy of continuous PD-1 inhibitor therapy beyond PD might be limited.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.