Overview
Keytruda Qlex is approved by the U.S. Food and Drug Administration (FDA) for several types of non-small cell lung cancer (NSCLC). It is approved in combination with pemetrexed and a platinum-based chemotherapy for adults with metastatic nonsquamous NSCLC whose tumors do not have EGFR or ALK gene mutations (changes). It is also approved in combination with carboplatin and either paclitaxel or paclitaxel protein-bound for adults with metastatic squamous NSCLC.

Keytruda Qlex is also approved as a single agent for adults whose tumors express PD-L1 (as determined by an FDA-approved test) and have no EGFR or ALK tumor mutations when the disease is stage 3 (for those who are not candidates for surgical resection or chemoradiation) or metastatic. It is also approved as a single agent for adults with PD-L1–positive metastatic NSCLC that has progressed after platinum-containing chemotherapy.

In addition, it is approved for resectable NSCLC in combination with platinum-containing chemotherapy as neoadjuvant treatment, then continued as a single agent as adjuvant treatment after surgery. It is also approved as a single agent for adjuvant treatment following resection and platinum-based chemotherapy for eligible stages. Keytruda Qlex is also known by its drug name, pembrolizumab and berahyaluronidase alfa-pmph.

Keytruda Qlex is a type of immunotherapy. It works by blocking the PD-1 protein on immune cells, which helps the immune system recognize and attack lung cancer cells. Berahyaluronidase alfa helps the medication absorb more efficiently when injected under the skin.

How do I take it?
Prescribing information states that Keytruda Qlex is given as a subcutaneous (under the skin) injection into the abdomen or thigh by a healthcare provider. It is typically administered once every three or six weeks, depending on the dosing schedule. It should be administered exactly as prescribed by a healthcare provider.

Side effects
Common side effects of Keytruda Qlex include fatigue, nausea, musculoskeletal pain (pain in muscles, bones, or joints), rash, diarrhea, decreased appetite, cough, shortness of breath, constipation, abdominal pain, fever, itching, and hypothyroidism (low thyroid hormone levels). 

When used with chemotherapy, side effects may also include vomiting, hair loss, peripheral neuropathy (nerve damage causing pain or numbness), mouth sores, weight loss, joint pain, muscle pain, insomnia, hand-foot syndrome (skin reaction on palms and soles), urinary tract infections, and inflammation of mucous membranes.

Rare but serious side effects may include immune-mediated reactions such as pneumonitis (lung inflammation), colitis (intestinal inflammation), hepatitis (liver inflammation), endocrinopathies (hormone gland problems), nephritis (kidney inflammation), severe skin reactions, and rejection of transplanted organs. Severe allergic reactions and complications following stem cell transplant may also occur. The drug may cause harm to an unborn baby and is not recommended during pregnancy.

For more information about this treatment, visit:

Keytruda Qlex (Pembrolizumab and Berahyaluronidase Alfa-Pmph) Injection, for Subcutaneous Use — Merck Sharp & Dohme