Samsung Bioepis Co., Ltd. recently announced that the U.S. Food and Drug Administration (FDA) has approved Ontruzant (trastuzumab-dttb), a biosimilar referencing Herceptin®i (trastuzumab), across all eligible indications, namely adjuvant treatment of HER2-overexpressing breast cancer, metastatic breast cancer and metastatic gastric cancer or gastroesophageal junction adenocarcinoma in patients who have not received prior treatment for metastatic disease.

 “For many cancer patients in the US, battling cancer has not only been a health issue, but a considerable financial burden brought on by cancer treatment. Biosimilars are intended to be lower cost, high-quality treatment options that have the potential to alleviate such burden. We sincerely hope our trastuzumab biosimilar will do exactly that,” said Sang-Jin Pak, Senior Vice President and Head of Commercial Division, Samsung Bioepis.

About Ontruzant (trastuzumab-dttb)

Ontruzant is indicated for adjuvant treatment of HER2-overexpressing node-positive or node-negative (ER/PR-negative or with one high-risk feature*) breast cancer:

As part of a treatment regimen containing doxorubicin, cyclophosphamide and either paclitaxel or docetaxel

With docetaxel and carboplatin

As a single agent following multi-modality anthracycline-based therapy

Select patients for therapy based on an FDA-approved companion diagnostic for a trastuzumab product.

High-risk is defined as ER/PR positive with one of the following features: tumor size >2 cm, age <35 years, or tumor grade 2 or 3.

Ontruzant is indicated:

In combination with paclitaxel for the first line treatment of HER2-overexpressing metastatic breast cancer

As a single agent for treatment of HER2-overexpressing breast cancer in patients who have received one or more chemotherapy regimens for metastatic disease

Select patients for therapy based on an FDA-approved companion diagnostic for a trastuzumab product.

Important safety information

Cardiomyopathy

Ontruzant administration can result in sub-clinical and clinical cardiac failure manifesting as congestive heart failure and decreased left ventricular ejection fraction with greatest risk when administered concurrently with anthracyclines. Evaluate cardiac function prior to and during treatment. Discontinue Ontruzant for cardiomyopathy.

Infusion reactions; Pulmonary toxicity

Administration can result in serious and fatal infusion reactions and pulmonary toxicity. Symptoms usually occur during or within 24 hours of administration. Discontinue Ontruzant for anaphylaxis, angioedema, interstitial pneumonitis, or acute respiratory distress syndrome.

Embryo-fetal toxicity

Exposure to Ontruzant during pregnancy can result in oligohydramnios in some cases complicated by pulmonary hypoplasia, skeletal abnormalities, and neonatal death. Advise patients of these risks and the need for effective contraception

Exacerbation of chemotherapy-induced Neutropenia

In randomized, controlled clinical trials, the per-patient incidences of NCI-CTC Grade 3-4 neutropenia and of febrile neutropenia were higher in patients receiving trastuzumab products in combination with myelosuppressive chemotherapy as compared to those who received chemotherapy alone. The incidence of septic death was similar among patients who received trastuzumab and those who did not

Most common adverse reactions

The most common adverse reactions for trastuzumab products in breast cancer were fever, nausea, vomiting, infusion reactions, diarrhea, infections, increased cough, headache, fatigue, dyspnea, rash, neutropenia, anemia, and myalgia

The most common adverse reactions for trastuzumab products in metastatic gastric cancer were neutropenia, diarrhea, fatigue, anemia, stomatitis, weight loss, upper respiratory tract infections, fever, thrombocytopenia, mucosal inflammation, nasopharyngitis, and dysgeusia

These are not all of the risks associated with Ontruzant®.