24 Real-world Use of Neratinib Post-Pertuzumab (P) and –Ado-Trastuzumab Emtansine (T-DM1)

Background

Neratinib’s (Nerlynx) pivotal study was performed before pertuzumab (Perjeta) and trastuzumab emtansine (Kadcyla; T-DM1) adjuvant approvals. There is interest in neratinib’s treatment patterns after pertuzumab and T-DM1 use. Neat-HER was a United States virtual registry pilot of patients with early HER2-positive breast cancer (EBC) receiving neratinib as extended adjuvant therapy in clinical practice.

Methods

Eligibility included age 18 years and older and no clinical trial participation. Patients were recruited mainly through social media, patient advocacy group and the Puma patient texting program. Electronic health records (EHRs) for EBC treatment were collected 7 years pre- to 1 year post enrollment. We evaluated personal/tumor characteristics for those who did and did not receive neoadjuvant therapy and treatment received. Treatment information came from EHR via machine learning with physician review. Neratinib status and start/stop dates were abstracted from the physician narrative, and duration of neratinib treatment was the difference between the start and stop dates, inclusive of dose holds.

Results

Forty-six patients with EBC who received neratinib as extended adjuvant treatment enrolled in the registry in December 2018. The majority, 76% (n = 35), had neoadjuvant therapy with adjuvant treatment and 24% (n = 11) had only adjuvant treatment. Median age (50 vs 48 years) and race (91% White) were similar for neoadjuvant and adjuvant-only patients. Treatment settings were mostly in the South (52% overall), followed by the Midwest (22% overall). Among neoadjuvant therapy patients, 80% had hormone receptor (ER/PR)-positive and 74% had lymph node–positive EBC. In adjuvant-only patients, 91% had hormone receptor–positive and 46% had lymph node–positive EBC. Fifty-four percent of neoadjuvant therapy (vs 82% adjuvant only patients) had high-grade EBC. The most common neoadjuvant therapy agents used were in order: taxanes, trastuzumab, pertuzumab, and platinum. For adjuvant treatment, pertuzumab use was less frequent (34% vs 64% of pateints) and T-DM1 use more frequent (14% vs 0%) among neoadjuvant therapy patients vs those with only adjuvant treatment. Median duration of neratinib treatment in patients who had received neoadjuvant therapy was 12 months (mean, 11 months) with 94% of these patients completing or having ongoing treatment. In patients who received adjuvant treatment, only 55% of patients either completed or had ongoing neratinib treatment at the time of this analysis.

Conclusions

Neat-HER provided useful information on neoadjuvant therapy/adjuvant treatment patterns in patients receiving extended adjuvant neratinib. It was the first known examination of real-world treatment patterns of neratinib post pertuzumab and T-DM1. The high proportion of neoadjuvant therapy use and long duration of neratinib suggest the select nature of these patients. Results need to be reproduced in larger patient cohorts.

Author Affiliations:

Kathryn Martin,¹ Hope S. Rugo² Gregory Vidal,³ Nina Oestreicher,¹ Deepa Lalla,¹ Gillian Hanson,⁴ Daniel Drozd,⁴ Kristie Traverso,¹ Dan DiPrimeo,¹ Debu Tripathy⁵

¹Puma Biotechnology, Los Angeles, CA

²University of California, San Francisco, Helen Diller Family Comprehensive Cancer Center, San Francisco, CA

³West Cancer Center and Research Institute, Memphis, TN

⁴Picnic Health, San Francisco, CA

⁵Department of Breast Medical Oncology, Division of Cancer Medicine, MD Anderson Cancer Center, Houston, TX