Seagen Announces Positive CHMP Opinion for Tucatinib for the Treatment of Patients with Locally Advanced or Metastatic HER2-Positive Breast Cancer

- Recommendation for Approval in the European Union Based on Results of Pivotal HER2CLIMB Trial -

ZUG, Switzerland, 11 December 2020 – Seagen Inc. (Nasdaq:SGEN) today announced that the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency adopted a positive opinion recommending approval for tucatinib in combination with trastuzumab and capecitabine for the treatment of adult patients with HER2-positive locally advanced or metastatic breast cancer who have received at least two prior anti-HER2 treatment regimens.[i]

The CHMP positive opinion will now be considered by the European Commission (EC), which has the authority to approve medicines in the European Union (EU). Tucatinib is approved in the United States, Canada, Switzerland, Singapore and Australia.

“We are pleased the CHMP has recognized tucatinib as a meaningful clinical advance for people with advanced HER2-positive metastatic breast cancer, including those with cancer that has spread to the brain,” said Roger Dansey, M.D., Chief Medical Officer at Seagen. “This opinion brings us one step closer to making tucatinib available to patients in the EU and reinforces our commitment to bring innovative therapies to patients around the world.” 

The positive CHMP opinion is based on results of the pivotal trial HER2CLIMB and which were published in The New England Journal of Medicine in December 2019.

About HER2CLIMB

HER2CLIMB is a randomized, double-blind, placebo-controlled, active comparator, global trial that enrolled 612 patients with HER2-positive unresectable locally advanced or metastatic breast cancer who had previously received, either separately or in combination, trastuzumab, pertuzumab, and ado-trastuzumab emtansine (T-DM1). The results for the primary endpoint showed patients who received tucatinib in combination with trastuzumab and capecitabine had a 46 percent reduction in the risk of cancer progression or death (PFS) compared to patients who received trastuzumab and capecitabine alone (hazard ratio (HR)=0.54 [95% Confidence Interval (CI): 0.42, 0.71]; p<0.00001). A secondary endpoint showed that the addition of tucatinib reduced the risk of death (OS) by 34 percent compared to trastuzumab and capecitabine alone (HR=0.66 [95% CI: 0.50, 0.87]; p=0.0048). Based on the results, tucatinib was approved as TUKYSA^® in the U.S. in combination with trastuzumab and capecitabine for treatment of adult patients with advanced unresectable or metastatic HER2-positive breast cancer, including patients with brain metastases, who have received one or more prior anti-HER2-based regimens in the metastatic setting.

About HER2-Positive Breast Cancer

Patients with HER2-positive breast cancer have tumors with high levels of a protein called human epidermal growth factor receptor 2 (HER2), which promotes the growth of cancer cells. In 2018, more than two million new cases of breast cancer were diagnosed worldwide, including 522,513 in Europe.[ii] Between 15 and 20 percent of breast cancer cases are HER2-positive.[iii] Historically, HER2-positive breast cancer tends to be more aggressive and more likely to recur than HER2-negative breast cancer.[iv]^,[iii],[v] Up to 50 percent of metastatic HER2-positive breast cancer patients develop brain metastases over time.[vi]^,[vii]^,[viii]

About Tucatinib

Tucatinib is an oral medicine that is a tyrosine kinase inhibitor of the HER2 protein. In vitro (in lab studies), tucatinib inhibited phosphorylation of HER2 and HER3, resulting in inhibition of downstream MAPK and AKT signaling and cell growth (proliferation), and showed anti-tumor activity in HER2-expressing tumor cells. In vivo (in living organisms), tucatinib inhibited the growth of HER2-expressing tumors. 

About Seagen

Seagen is a global biotechnology company that discovers, develops and commercializes transformative cancer medicines to make a meaningful difference in people’s lives. Seagen is headquartered in the Seattle, Washington area, and has locations in California, Canada, Switzerland and the European Union. For more information on the company’s marketed products and robust pipeline, visit www.seagen.com and follow @SeagenGlobal on Twitter.

[i] European Medicines Agency. TUKYSA Summary of Opinion. https://www.ema.europa.eu/en/documents/smop-initial/chmp-summary-positive-opinion-tukysa_en.pdf

[ii] Breast. Globocan 2018. World Health Organization. 2019. https://gco.iarc.fr/today/data/factsheets/cancers/20-Breast-fact-sheet.pdf

[iii] Slamon D, Clark G, Wong S, et al. Human breast cancer: correlation of relapse and survival with amplification of the HER-2/neu onco­gene. Science. 1987; 235(4785): 177-82.

[iv] Loibli S, Gianni L. HER2-positive breast cancer. Lancet. 2017; 389(10087): 2415-29.

[v] Breast Cancer HER2 Status. American Cancer Society website. https://www.cancer.org/cancer/breast-cancer/understanding-a-breast-cancer-diagnosis/breast-cancer-her2-status.html. Accessed March 9, 2020.

[vi] Freedman RA, Gelman RS, Anders CK, et al. TBCRC 022: a phase II trial of neratinib and capecitabine for patients with human epidermal growth factor receptor 2-positive breast cancer and brain metastases. J Clin Oncol. 2019;37:1081-1089.

[vii] Olson EM, Najita JS, Sohl J, et al. Clinical outcomes and treatment practice patterns of patients with HER2-positive metastatic breast cancer in the post-trastuzumab era. Breast. 2013;22:525-531.

[viii] Bendell JC, Domchek SM, Burstein HJ, et al. Central nervous system metastases in women who receive trastuzumab-based therapy for metastatic breast carcinoma. Cancer. 2003;97:2972-2977.