At a median follow-up of 43.7 months 85.6% of patients treated with durvalumab survived cancer free compared to 77.2% of those not receiving durvalumab. At the 2021 Annual Meeting of the American Society of Clinical Oncology, the investigators reported the results of longer-term outcomes. A numerical increase in the pCR rate was initially reported with durvalumab compared to placebo (53.4% vs.
#Keynote 355 trial
In this trial patients with stage I-III TNBC were treated with durvalumab or placebo, in combination with nab-paclitaxel plus epirubicin and cyclophosphamide chemotherapy. The GeparNuevo clinical trial evaluated whether the addition of Imfinzi (durvalumab), a PD-L1 antibody, to neoadjuvant chemotherapy would increase the rate of pathologic complete response (pCR) in patients with early-stage TNBC. Imfinzi (durvalumab) Effective as Neoadjuvant Treatment for Stage I-III TNBC The benefit seen with the Keytruda regimen was independent of PD-L1 expression and this lead to FDA approval. 10 Updated results at three years remain positive: 84.5% of patients treated with the Keytruda regimen survive without cancer progression compared to 76.8% of patients treated with chemotherapy and no Keytruda. Overall 65% off Keytruda treated patients had a pathologic complete remission compared to only 51 % of women not treated with Keytruda and 91% survived without evidence of cancer compared to 85% at the time of this analyses.
Analyses revealed that Keytruda treated patents were less likely to have evidence of cancer in their surgically removed breast tissue and more likely to survive without evidence of cancer recurrence. After completion of local therapy patients were treated with additional Keytruda. This was confirmed in the KEYNOTE 522 clinical trial which enrolled 1,174 patients with locally advanced TNBC to receive treatment with standard chemotherapy with or without the addition of Keytruda followed by definitive surgery and radiation therapy.