On Saturday 3 October Dr Paolo Nuciforo presented the nine-year event free survival (EFS) and overall survival (OS) rates of the NeoALTTO trial (BIG 1-06), with a highlight on the relationship between survival and pathological complete response (pCR) in the overall population and according to hormonal receptor status and treatment arm.
This long-term analysis, based on a median follow up of 9.7 years, showed that women who achieved pCR have significantly higher survival rates (EFS and OS) compared to those who did not. It confirms that pCR is likely an indicator of long-term benefit in HER2-positive breast cancer. This trend is more important in patients whose disease is hormone receptor-negative and in the population receiving the combination of lapatinib and trastuzumab. In the overall population, the survival rates by treatment arm did not differ significantly; however, patients who reached a pCR in the combination arm were nearly double compared to patients in the single drug arms. The analysis did not report any new or long-term safety concerns.
Developed in parallel with its sister trial ALTTO (BIG 2-06), the NeoALTTO study included 455 patients and was set up to investigate whether combining trastuzumab (Herceptin®) with another drug called lapatinib (Tykerb®) – given either alone, together or one after the other – could benefit patients with HER2-positive primary breast cancer in the neoadjuvant (pre-surgical) setting. To our knowledge, NeoALTTO is the neoadjuvant study with dual HER2 blockade in early breast cancer with the longest clinical follow-up (almost 10 years).
NeoALTTO is a study co-led by SOLTI Breast Cancer Group, BIG Headquarters, Institut Jules Bordet’s Clinical Trials Support Unit (IJB-CTSU) and Frontier Science & Technology Research Foundation (FSTRF). The primary analysis, published in the Lancet in 2012, showed that dual HER2-targeted therapy with lapatinib and trastuzumab resulted in more patients achieving a pCR, meaning a disappearance of all visible signs of cancer, compared to a single HER2-targeted therapy (trastuzumab).
Reference: Nuciforo P, Townend J, Saura C et al. Nine-year survival outcome of neoadjuvant lapatinib with trastuzumab for HER2-positive breast cancer (NeoALTTO, BIG 1-06): final analysis of a multicentre, open-label, phase 3 randomised clinical trial. Abstract no 23, proffered papers session