FDA Approves Keytruda (pembrolizumab) for First-Line Treatment of Head and Neck Squamous Cell Carcinoma

By | June 13, 2019

KENILWORTH, N.J.–(BUSINESS WIRE) June 11, 2019 –Merck (NYSE: MRK), known as MSD outside the United States and Canada, today announced that the U.S. Food and Drug Administration (FDA) has approved Keytruda, Merck’s anti-PD-1 therapy, as monotherapy in patients whose tumors express PD-L1 (Combined Positive Score [CPS] ≥1) or in combination with platinum and fluorouracil (FU), a commonly used chemotherapy regimen, for the first-line treatment of patients with metastatic or with unresectable, recurrent head and neck squamous cell carcinoma (HNSCC). The approval is based on results from the pivotal Phase 3 KEYNOTE-048 trial, where Keytruda demonstrated a significant improvement in overall survival (OS) compared with the EXTREME regimen (cetuximab with carboplatin or cisplatin plus FU), a standard treatment, as monotherapy in patients whose tumors expressed PD-L1 (CPS ≥1) (HR=0.78 [95% CI, 0.64-0.96]; p=0.0171) and in combination with chemotherapy in the total study population (HR=0.77 [95% CI, 0.63-0.93]; p=0.0067). With these new indications, Keytruda is the first anti-PD-1 therapy approved in the first-line setting as monotherapy in patients whose tumors express PD-L1 (CPS ≥1) or in combination with chemotherapy regardless of PD-L1 expression for patients with metastatic or with unresectable, recurrent HNSCC and the first anti-PD-1 therapy to demonstrate a statistically significant improvement in OS in these patients.

“This approval is a very exciting milestone in the treatment of head and neck cancer and has the potential to transform the way we treat patients with this debilitating disease by offering important new therapeutic options,” said Dr. Barbara Burtness, professor of medicine, Yale School of Medicine and co-director, Development Therapeutics Research Program, Yale Cancer Center. “Metastatic or recurrent head and neck cancer has been an area of significant unmet need, so it is encouraging to have immunotherapy regimens available for patients in the first-line setting.”

Immune-mediated adverse reactions, which may be severe or fatal, can occur with Keytruda, including pneumonitis, colitis, hepatitis, endocrinopathies, nephritis and renal dysfunction, severe skin reactions, solid organ transplant rejection, and complications of allogeneic hematopoietic stem cell transplantation (HSCT). Based on the severity of the adverse reaction, Keytruda should be withheld or discontinued and corticosteroids administered if appropriate. Keytruda can also cause severe or life-threatening infusion-related reactions. Based on its mechanism of action, Keytruda can cause fetal harm when administered to a pregnant woman. For more information, see “Selected Important Safety Information” below.

“Head and neck squamous cell carcinoma has historically presented many challenges to physicians and patients, including limited treatment options and physical and functional issues caused by the disease and its treatment,” said Dr. Jonathan Cheng, vice president, clinical research, Merck Research Laboratories. “This approval is an important advance in the management of this devastating cancer. The results of KEYNOTE-048, which support this approval, demonstrated that Keytruda monotherapy for patients whose tumors expressed PD-L1 CPS greater than or equal to one and Keytruda in combination with chemotherapy regardless of PD-L1 expression significantly prolonged survival for patients with metastatic or with unresectable, recurrent head and neck squamous cell carcinoma in the first-line setting.”

Keytruda was initially approved for the treatment of patients with recurrent or metastatic HNSCC with disease progression on or after platinum-containing chemotherapy in 2016 under the FDA’s accelerated approval process based on objective response rate data from the Phase 1b KEYNOTE-012 trial. In accordance with the accelerated approval process, continued approval was contingent upon verification and description of clinical benefit, which has now been demonstrated in KEYNOTE-048 and has resulted in the FDA converting the accelerated approval to a full (regular) approval.

Data Supporting the Approval

This approval is based on data from the pre-specified interim analysis of the Phase 3 KEYNOTE-048 trial, a randomized, multi-center, open-label, active-controlled trial conducted in 882 patients with metastatic HNSCC who had not previously received systemic therapy and who were considered incurable by local therapies. Randomization was stratified by tumor PD-L1 expression (Tumor Proportion Score [TPS] ≥50% or <50%) according to the PD-L1 IHC 22C3 pharmDx kit, HPV status according to p16 IHC (positive or negative), and ECOG Performance Status (PS) (0 vs. 1). Patients were randomized 1:1:1 to one of the following treatment arms:

  • Keytruda 200 mg intravenously every three weeks;
  • Keytruda 200 mg intravenously every three weeks, carboplatin AUC 5 mg/mL/min intravenously every three weeks or cisplatin 100 mg/m2 intravenously every three weeks and FU 1000 mg/m2/day as a continuous intravenous infusion over 96 hours every three weeks (maximum of six cycles of platinum and FU);
  • Cetuximab 400 mg/m2 intravenously as the initial dose then 250 mg/m2 intravenously once weekly, carboplatin AUC 5 mg/mL/min intravenously every three weeks or cisplatin 100 mg/m2 intravenously every three weeks and FU 1000 mg/m2/day as a continuous intravenous infusion over 96 hours every three weeks (maximum of six cycles of platinum and FU).

Among the 882 patients, the study population characteristics were: median age of 61 years (range, 20 to 94), 36% age 65 or older; 83% male; 73% White, 20% Asian, and 2.4% Black; 61% had ECOG PS of 1; and 79% were former or current smokers. Twenty-two percent of patients’ tumors were HPV positive; 23% had PD-L1 TPS ≥50%; and 95% had stage IV disease (19% were stage IVA, 6% were stage IVB, and 70% were stage IVC). Eighty-five percent of patients’ tumors had PD-L1 expression of CPS ≥1, and 43% had CPS ≥20.

Treatment with Keytruda continued until RECIST v1.1-defined progression of disease as determined by the investigator, unacceptable toxicity or a maximum of 24 months. A retrospective re-classification of patients’ tumor PD-L1 status according to CPS using the PD-L1 IHC 22C3 pharmDx kit was conducted using the tumor specimens used for randomization.

The main efficacy outcome measures were OS and progression-free survival (PFS) as assessed by blinded independent central review (BICR) according to RECIST v1.1 (modified to follow a maximum of 10 target lesions and a maximum of five target lesions per organ) sequentially tested in the subgroup of patients with CPS ≥20, the subgroup of patients with CPS ≥1 and the overall population.

Efficacy Results for Keytruda as a Single Agent in KEYNOTE-048 (CPS ≥1 and CPS ≥20)

             
Endpoint     CPS ≥1     CPS ≥20
    KEYTRUDA

200 mg every 3 weeks

n=257

    Cetuximab

Platinum

FU

n=255

    KEYTRUDA

200 mg every 3 weeks

n=133

    Cetuximab

Platinum

FU

n=122

OS
Number of events (%)     177 (69%)     206 (81%)     82 (62%)     95 (78%)
Median in months (95% CI)     12.3

(10.8, 14.9)

    10.3 (9.0,11.5)     14.9

(11.6, 21.5)

    10.7

(8.8, 12.8)

Hazard ratio* (95% CI)     0.78 (0.64, 0.96)     0.61 (0.45, 0.83)
p-Value     0.0171     0.0015
PFS
Number of events (%)     225 (88%)     231 (91%)     113 (85%)     111 (91%)
Median in months (95% CI)     3.2 (2.2, 3.4)     5.0 (4.8, 5.8)     3.4 (3.2, 3.8)     5.0 (4.8, 6.2)
Hazard ratio (95% CI)     1.15 (0.95, 1.38)     0.99 (0.75, 1.29)
Objective Response Rate
ORR (95% CI)     19%

(14.5, 24.4)

    35%

(29.1, 41.1)

    23%

(16.4, 31.4)

    36%

(27.6, 45.3)

Complete response rate     5%     3%     8%     3%
Partial response rate     14%     32%     16%     33%
Duration of Response
Median in months (range)     20.9

(1.5+, 34.8+)

    4.5

(1.2+, 28.6+)

    20.9

(2.7, 34.8+)

    4.2

(1.2+, 22.3+)

* Based on the stratified Cox proportional hazard model

Based on a stratified log-rank test

Response: Best objective response as confirmed complete response or partial response

 

Efficacy Results for Keytruda plus Platinum/Fluorouracil in KEYNOTE-048

             
Endpoint     KEYTRUDA

200 mg every 3 weeks

Platinum

FU

n=281

    Cetuximab

Platinum

FU

n=278

OS
Number (%) of patients with event     197 (70%)     223 (80%)
Median in months (95% CI)     13.0

(10.9, 14.7)

    10.7

(9.3, 11.7)

Hazard ratio* (95% CI)     0.77 (0.63, 0.93)
p-Value     0.0067
PFS
Number of patients with event (%)     244 (87%)     253 (91%)
Median in months (95% CI)     4.9 (4.7, 6.0)     5.1 (4.9, 6.0)
Hazard ratio* (95% CI)     0.92 (0.77, 1.10)
p-Value     0.3394
Objective Response Rate
ORR(95% CI)     36%

(30.0, 41.5)

    36%

(30.7, 42.3)

Complete response rate     6%     3%
Partial response rate     30%     33%
Duration of Response
Median in months (range)     6.7

(1.6+, 30.4+)

    4.3

(1.2+, 27.9+)

* Based on the stratified Cox proportional hazard model

Based on stratified log-rank test

Response: Best objective response as confirmed complete response or partial response

 

In KEYNOTE-048, the safety of Keytruda, as a single agent and in combination with platinum (cisplatin or carboplatin) and FU chemotherapy, was investigated in patients with previously untreated, recurrent or metastatic HNSCC. The median duration of exposure to Keytruda 200 mg every three weeks was 3.5 months (range, 1 day to 24.2 months) in the Keytruda single agent arm and was 5.8 months (range, 3 days to 24.2 months) in the combination arm.

Keytruda was discontinued for adverse reactions in 12% of patients in the Keytruda single agent arm. The most common adverse reactions resulting in permanent discontinuation of Keytruda were sepsis (1.7%) and pneumonia (1.3%). Adverse reactions leading to the interruption of Keytruda occurred in 31% of patients; the most common adverse reactions leading to the interruption of Keytruda (≥2%) were pneumonia (2.3%), pneumonitis (2.3%) and hyponatremia (2%). The most common adverse reactions (≥20%) with Keytruda as a single agent were fatigue (33%), constipation (20%), and rash (20%).

Keytruda was discontinued for adverse reactions in 16% of patients in the combination arm. The most common adverse reactions resulting in permanent discontinuation of Keytruda were pneumonia (2.5%), pneumonitis (1.8%) and septic shock (1.4%). Adverse reactions leading to the interruption of Keytruda occurred in 45% of patients; the most common adverse reactions leading to interruption of Keytruda (≥2%) were neutropenia (14%), thrombocytopenia (10%), anemia (6%), pneumonia (4.7%) and febrile neutropenia (2.9%). The most common adverse reactions (≥20%) with Keytruda in combination with platinum and FU were nausea (51%), fatigue (49%), constipation (37%), vomiting (32%), mucosal inflammation (31%), diarrhea (29%), decreased appetite (29%), stomatitis (26%) and cough (22%).

About Keytruda (pembrolizumab) Injection

Keytruda is an anti-PD-1 therapy that works by increasing the ability of the body’s immune system to help detect and fight tumor cells. Keytruda is a humanized monoclonal antibody that blocks the interaction between PD-1 and its ligands, PD-L1 and PD-L2, thereby activating T lymphocytes which may affect both tumor cells and healthy cells.

Merck has the industry’s largest immuno-oncology clinical research program. There are currently more than 1,000 trials studying Keytruda across a wide variety of cancers and treatment settings. The Keytruda clinical program seeks to understand the role of Keytruda across cancers and the factors that may predict a patient’s likelihood of benefitting from treatment with Keytruda, including exploring several different biomarkers.

Merck’s Focus on Cancer

Our goal is to translate breakthrough science into innovative oncology medicines to help people with cancer worldwide. At Merck, the potential to bring new hope to people with cancer drives our purpose and supporting accessibility to our cancer medicines is our commitment. As part of our focus on cancer, Merck is committed to exploring the potential of immuno-oncology with one of the largest development programs in the industry across more than 30 tumor types. We also continue to strengthen our portfolio through strategic acquisitions and are prioritizing the development of several promising oncology candidates with the potential to improve the treatment of advanced cancers. For more information about our oncology clinical trials, visit www.merck.com/clinicaltrials.

About the Merck Access Program for Keytruda

At Merck, we are committed to supporting accessibility to our cancer medicines. Merck provides multiple programs to help appropriate patients who are prescribed Keytruda have access to our anti-PD-1 therapy. The Merck Access Program provides reimbursement support for patients receiving Keytruda, including information to help with out-of-pocket costs and co-pay assistance for eligible patients. More information is available by calling 855-257-3932 or visiting www.merckaccessprogram-keytruda.com.

About Merck’s Patient Support Program for Keytruda

Merck is committed to helping provide patients and their caregivers support throughout their treatment with KEYTRUDA. The KEY+YOU Patient Support Program provides a range of resources and support. For further information and to sign up, eligible patients may call 85-KEYTRUDA (855-398-7832) or visit www.keytruda.com.

About Merck

For more than a century, Merck, a leading global biopharmaceutical company known as MSD outside of the United States and Canada, has been inventing for life, bringing forward medicines and vaccines for many of the world’s most challenging diseases. Through our prescription medicines, vaccines, biologic therapies and animal health products, we work with customers and operate in more than 140 countries to deliver innovative health solutions. We also demonstrate our commitment to increasing access to health care through far-reaching policies, programs and partnerships. Today, Merck continues to be at the forefront of research to advance the prevention and treatment of diseases that threaten people and communities around the world – including cancer, cardio-metabolic diseases, emerging animal diseases, Alzheimer’s disease and infectious diseases including HIV and Ebola. For more information, visit www.merck.com and connect with us on Twitter, Facebook, Instagram, YouTube and LinkedIn.

Forward-Looking Statement of Merck & Co., Inc., Kenilworth, N.J., USA

This news release of Merck & Co., Inc., Kenilworth, N.J., USA (the “company”) includes “forward-looking statements” within the meaning of the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995. These statements are based upon the current beliefs and expectations of the company’s management and are subject to significant risks and uncertainties. There can be no guarantees with respect to pipeline products that the products will receive the necessary regulatory approvals or that they will prove to be commercially successful. If underlying assumptions prove inaccurate or risks or uncertainties materialize, actual results may differ materially from those set forth in the forward-looking statements.

Risks and uncertainties include but are not limited to, general industry conditions and competition; general economic factors, including interest rate and currency exchange rate fluctuations; the impact of pharmaceutical industry regulation and health care legislation in the United States and internationally; global trends toward health care cost containment; technological advances, new products and patents attained by competitors; challenges inherent in new product development, including obtaining regulatory approval; the company’s ability to accurately predict future market conditions; manufacturing difficulties or delays; financial instability of international economies and sovereign risk; dependence on the effectiveness of the company’s patents and other protections for innovative products; and the exposure to litigation, including patent litigation, and/or regulatory actions.

The company undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise. Additional factors that could cause results to differ materially from those described in the forward-looking statements can be found in the company’s 2018 Annual Report on Form 10-K and the company’s other filings with the Securities and Exchange Commission (SEC) available at the SEC’s Internet site ( www.sec.gov ).

Please see Prescribing Information for Keytruda at http://www.merck.com/product/usa/pi_circulars/k/keytruda/keytruda_pi.pdf and Medication Guide for Keytruda at http://www.merck.com/product/usa/pi_circulars/k/keytruda/keytruda_mg.pdf .

Source: Merck

Posted: June 2019

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