"We continue to build on our leadership in advanced melanoma by evaluating KEYTRUDA with multiple combination partners utilizing diverse mechanisms of action with the goal of improving outcomes while maintaining tolerability," said Dr. Roger Dansey, senior vice president and therapeutic area head, oncology late-stage development, Merck Research Laboratories. "These encouraging early data point to the potential for KEYTRUDA to become an important component of combination therapy in melanoma."
Each of these studies was designed to answer specific questions around the use of KEYTRUDA in various combination treatment settings. In each of the three studies, the safety profile of the combination regimens was shown to be manageable.
"Anti-PD-1 drug therapies, like pembrolizumab, have shown benefit as a monotherapy in the treatment of advanced melanoma, and it is important to understand their potential in combination with other effective therapeutics, including immunotherapies and targeted therapies," said Dr. Georgina Long, professor of melanoma medical oncology and translational melanoma research, Melanoma Institute Australia and University of Sydney. "Physicians are focused on different treatment paths for different types of patients and, with the promising data presented at ASCO this year, we aim to better understand the role of monotherapy and develop combination treatment strategies for patients with advanced melanoma who may not benefit as much from monotherapy."
The KEYTRUDA (pembrolizumab) clinical development program includes patients with more than 30 tumor types in more than 270 ongoing or planned studies, including more than 100 trials that combine KEYTRUDA with other cancer treatments - these include other immuno-oncology therapies, standard therapies and targeted therapies.
Findings from MASTERYKEY-265: KEYTRUDA with talimogene laherparepvec (Abstract #9568)
MASTERKEY-265 is an ongoing phase 1b study evaluating the safety, efficacy, and tolerability of KEYTRUDA in combination with talimogene laherparepvec in patients with previously untreated, unresectable advanced melanoma. The trial is a collaboration between Merck and Amgen. Talimogene laherparepvec is a herpes simplex virus-1 (HSV-1)-based oncolytic immunotherapy used for the treatment of melanoma lesions in the skin and lymph nodes.
Updated data from 21 evaluable patients showed that a combination of KEYTRUDA (200 mg every two weeks) with talimogene laherparepvec (up to 4 mL of 106 PFU/mL, then 108 PFU/mL every two weeks) resulted in a confirmed overall response rate (ORR) of 57.1 percent (n=12/21) (95% CI, 34-78.2), per modified immune-related response criteria (irRC) - 23.8 percent were complete responses (n=5/21) and 33.3 percent were partial responses (n=7/21).
The safety profile of KEYTRUDA in combination with talimogene laherparepvec was consistent with that observed in previously reported studies of KEYTRUDA or talimogene laherparepvec monotherapy in patients with advanced melanoma. Seven patients (33%) experienced treatment-related Grade 3-4 adverse events, including: anemia, aseptic meningitis, autoimmune hepatitis, generalized rash, headache, hyperglycemia, hypoglycemia, hypophosphatemia, increased alanine aminotransferase, increased aspartate aminotransferase, increased gamma-glutamyltransferase, muscle spasms, macular rash, rash, and pneumonitis. Two patients (10%) experienced a treatment-related adverse event that led to permanent discontinuation of KEYTRUDA. No patients (0%) experienced a treatment-related adverse event that led to permanent discontinuation of talimogene laherparepvec. No dose-limiting toxicities were reported.
These data were presented by Dr. Long on June 4.
Findings from KEYNOTE-022: KEYTRUDA with dabrafenib plus trametinib (Abstract #3014)
KEYNOTE-022 is an ongoing phase 1/2 study designed to assess the safety and efficacy of KEYTRUDA in combination with dabrafenib plus trametinib in patients with advanced melanoma. Dabrafenib (a BRAF inhibitor) and trametinib (a MEK inhibitor) is a combination regimen used in the treatment of certain types of advanced melanoma.
Based on early data from the 15 patients treated in phase 1, treatment with KEYTRUDA (pembrolizumab) (2 mg/kg every three weeks) with dabrafenib (150 mg twice daily) plus trametinib (2 mg daily) resulted in nine partial responses, five of which were confirmed. Additionally, of the patients with lesion data available, 92.3 percent experienced a reduction in tumor size (n=12/13).
Grade 3-4 adverse events occurring in greater than or equal to 10 percent of patients included ALT increased (n=3), AST increased (n=3), pyrexia (n=3), GGT increased (n=2), and WBC count decreased (n=2). Four patients (26.7%) experienced a treatment-related adverse even that led to discontinuation. There were no treatment-related deaths. The phase 2 part of the study is ongoing and will further evaluate the safety and efficacy of the KEYTRUDA combination regimen compared to dabrafenib plus trametinib.
On June 5, these data will be presented by Dr. Antoni Ribas in a poster session from 8:00 - 11:30 a.m. CDT (Location: Hall A) and in a poster discussion from 4:45 - 6:00 p.m. CDT (Location: Hall B1).
Findings from KEYNOTE-029: KEYTRUDA with low-dose ipilimumab (Abstract #9506)
KEYNOTE-029 is an ongoing phase 1/2 study evaluating the safety, efficacy, and tolerability of KEYTRUDA in combination with low-dose ipilimumab in patients with advanced melanoma. Ipilimumab is a CTLA-4 inhibitor used in the treatment of melanoma.
Findings from 153 evaluable patients with advanced melanoma showed that KEYTRUDA (2 mg/kg every three weeks) in combination with low-dose ipilimumab (1 mg/kg every three weeks for four doses) demonstrated an ORR of 57 percent (95% CI, 49-65) by independent central review - 10 percent were complete responses (n=15/153) and 47 percent were partial responses (n=72/153). The six-month progression-free survival (PFS) rate was 70 percent and the six-month overall survival (OS) rate was 93 percent. At the time of analysis, median PFS (95% CI, 12.4 months-NR) and OS (95% CI, NR-NR) were not reached; 98 percent of responses were ongoing. Median follow-up duration was 10.0 months (range 0.8-14.1).
Sixty-four patients (42%) experienced treatment-related Grade 3-4 adverse events. Thirty-eight patients (25%) experienced immune-mediated Grade 3-4 adverse events, including: colitis, hepatitis, hyperthyroidism, hypophysitis, infusion reaction, pancreatitis, pneumonitis, nephritis, skin reactions, and type 1 diabetes mellitus. Sixteen patients (10%) experienced a treatment-related adverse event that led to ipilimumab discontinuation only, 11 patients (7%) experienced a treatment-related adverse event that led to KEYTRUDA (pembrolizumab) discontinuation after completion or discontinuation of ipilimumab, and 16 patients (10%) experienced a treatment-related adverse event that led to ipilimumab and KEYTRUDA discontinuation, including one patient who discontinued ipilimumab for colitis and later discontinued KEYTRUDA for increased lipase. There were no treatment-related deaths.
These data will be presented in an oral session by Dr. Long on June 6 at 2:51 p.m. CDT (Location: Arie Crown Theater).
About KEYTRUDA® (pembrolizumab) Injection 100 mg
KEYTRUDA is a humanized monoclonal antibody that works by increasing the ability of the body's immune system to help detect and fight tumor cells. KEYTRUDA 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.
KEYTRUDA is indicated for the treatment of patients with unresectable or metastatic melanoma.
KEYTRUDA is also indicated for the treatment of patients with metastatic non-small cell lung cancer (NSCLC) whose tumors express PD-L1 as determined by an FDA-approved test with disease progression on or after platinum-containing chemotherapy. Patients with EGFR or ALK genomic tumor aberrations should have disease progression on FDA-approved therapy for these aberrations prior to receiving KEYTRUDA. This indication is approved under accelerated approval based on tumor response rate and durability of response. An improvement in survival or disease-related symptoms has not yet been established. Continued approval for this indication may be contingent upon verification and description of clinical benefit in the confirmatory trials.
KEYTRUDA is administered at a dose of 2 mg/kg as an intravenous infusion over 30 minutes every three weeks for the approved indications.
Selected Important Safety Information for KEYTRUDA® (pembrolizumab)
Immune-mediated pneumonitis, including fatal cases, occurred in patients receiving KEYTRUDA. Pneumonitis occurred in 32 (2.0%) of 1567 patients, including Grade 1 (0.8%), 2 (0.8%), and 3 (0.4%) pneumonitis. Monitor patients for signs and symptoms of pneumonitis. Evaluate suspected pneumonitis with radiographic imaging. Administer corticosteroids for Grade 2 or greater pneumonitis. Withhold KEYTRUDA for Grade 2; permanently discontinue KEYTRUDA for Grade 3 or 4 or recurrent Grade 2 pneumonitis.
Immune-mediated colitis occurred in 31 (2%) of 1567 patients, including Grade 2 (0.5%), 3 (1.1%), and 4 (0.1%) colitis. Monitor patients for signs and symptoms of colitis. Administer corticosteroids for Grade 2 or greater colitis. Withhold KEYTRUDA (pembrolizumab) for Grade 2 or 3; permanently discontinue KEYTRUDA for Grade 4 colitis.
Immune-mediated hepatitis occurred in 16 (1%) of 1567 patients, including Grade 2 (0.1%), 3 (0.7%), and 4 (0.1%) hepatitis. Monitor patients for changes in liver function. Administer corticosteroids for Grade 2 or greater hepatitis and, based on severity of liver enzyme elevations, withhold or discontinue KEYTRUDA.
Hypophysitis occurred in 13 (0.8%) of 1567 patients, including Grade 2 (0.3%), 3 (0.3%), and 4 (0.1%) hypophysitis. Monitor patients for signs and symptoms of hypophysitis (including hypopituitarism and adrenal insufficiency). Administer corticosteroids and hormone replacement as clinically indicated. Withhold KEYTRUDA for Grade 2; withhold or discontinue for Grade 3 or 4 hypophysitis.
Hyperthyroidism occurred in 51 (3.3%) of 1567 patients, including Grade 2 (0.6%) and 3 (0.1%) hyperthyroidism. Hypothyroidism occurred in 127 (8.1%) of 1567 patients, including Grade 3 (0.1%) hypothyroidism. Thyroid disorders can occur at any time during treatment. Monitor patients for changes in thyroid function (at the start of treatment, periodically during treatment, and as indicated based on clinical evaluation) and for clinical signs and symptoms of thyroid disorders. Administer replacement hormones for hypothyroidism and manage hyperthyroidism with thionamides and beta-blockers as appropriate. Withhold or discontinue KEYTRUDA for Grade 3 or 4 hyperthyroidism.
Type 1 diabetes mellitus, including diabetic ketoacidosis, occurred in 3 (0.1%) of 2117 patients. Monitor patients for hyperglycemia or other signs and symptoms of diabetes. Administer insulin for type 1 diabetes, and withhold KEYTRUDA and administer anti-hyperglycemics in patients with severe hyperglycemia.
Immune-mediated nephritis occurred in 7 (0.4%) of 1567 patients, including Grade 2 (0.2%), 3 (0.2%), and 4 (0.1%) nephritis. Monitor patients for changes in renal function. Administer corticosteroids for Grade 2 or greater nephritis. Withhold KEYTRUDA for Grade 2; permanently discontinue KEYTRUDA for Grade 3 or 4 nephritis.
Other clinically important immune-mediated adverse reactions can occur. For suspected immune-mediated adverse reactions, ensure adequate evaluation to confirm etiology or exclude other causes. Based on the severity of the adverse reaction, withhold KEYTRUDA and administer corticosteroids. Upon improvement to Grade 1 or less, initiate corticosteroid taper and continue to taper over at least 1 month. Based on limited data from clinical studies in patients whose immune-related adverse reactions could not be controlled with corticosteroid use, administration of other systemic immunosuppressants can be considered. Resume KEYTRUDA when the adverse reaction remains at Grade 1 or less following corticosteroid taper. Permanently discontinue KEYTRUDA for any Grade 3 immune-mediated adverse reaction that recurs and for any life-threatening immune-mediated adverse reaction.
The following clinically significant, immune-mediated adverse reactions occurred in less than 1% (unless otherwise indicated) of 1567 patients: arthritis (1.6%), exfoliative dermatitis, bullous pemphigoid, uveitis, myositis, Guillain-Barré syndrome, myasthenia gravis, vasculitis, pancreatitis, hemolytic anemia, and partial seizures arising in a patient with inflammatory foci in brain parenchyma.
Severe and life-threatening infusion-related reactions have been reported in 3 (0.1%) of 2117 patients. Monitor patients for signs and symptoms of infusion-related reactions including rigors, chills, wheezing, pruritus, flushing, rash, hypotension, hypoxemia, and fever. For Grade 3 or 4 reactions, stop infusion and permanently discontinue KEYTRUDA (pembrolizumab).
Based on its mechanism of action, KEYTRUDA can cause fetal harm when administered to a pregnant woman. If used during pregnancy, or if the patient becomes pregnant during treatment, apprise the patient of the potential hazard to a fetus. Advise females of reproductive potential to use highly effective contraception during treatment and for 4 months after the last dose of KEYTRUDA.
In Trial 6, KEYTRUDA was discontinued due to adverse reactions in 9% of 555 patients; adverse reactions leading to discontinuation in more than one patient were colitis (1.4%), autoimmune hepatitis (0.7%), allergic reaction (0.4%), polyneuropathy (0.4%), and cardiac failure (0.4%). Adverse reactions leading to interruption of KEYTRUDA occurred in 21% of patients; the most common (≥1%) was diarrhea (2.5%). The most common adverse reactions with KEYTRUDA vs ipilimumab were fatigue (28% vs 28%), diarrhea (26% with KEYTRUDA), rash (24% vs 23%), and nausea (21% with KEYTRUDA). Corresponding incidence rates are listed for ipilimumab only for those adverse reactions that occurred at the same or lower rate than with KEYTRUDA.
In Trial 2, KEYTRUDA was discontinued due to adverse reactions in 12% of 357 patients; the most common (≥1%) were general physical health deterioration (1%), asthenia (1%), dyspnea (1%), pneumonitis (1%), and generalized edema (1%). Adverse reactions leading to interruption of KEYTRUDA occurred in 14% of patients; the most common (≥1%) were dyspnea (1%), diarrhea (1%), and maculo-papular rash (1%). The most common adverse reactions with KEYTRUDA vs chemotherapy were fatigue (43% with KEYTRUDA), pruritus (28% vs 8%), rash (24% vs 8%), constipation (22% vs 20%), nausea (22% with KEYTRUDA), diarrhea (20% vs 20%), and decreased appetite (20% with KEYTRUDA). Corresponding incidence rates are listed for chemotherapy only for those adverse reactions that occurred at the same or lower rate than with KEYTRUDA.
No formal pharmacokinetic drug interaction studies have been conducted with KEYTRUDA.
It is not known whether KEYTRUDA is excreted in human milk. Because many drugs are excreted in human milk, instruct women to discontinue nursing during treatment with KEYTRUDA and for 4 months after the final dose.
Safety and effectiveness of KEYTRUDA (pembrolizumab) have not been established in pediatric patients.
Our Focus on Cancer
Our goal is to translate breakthrough science into innovative oncology medicines to help people with cancer worldwide. At Merck Oncology, helping people fight cancer is our passion and supporting accessibility to our cancer medicines is our commitment. Our focus is on pursuing research in immuno-oncology and we are accelerating every step in the journey - from lab to clinic - to potentially bring new hope to people with cancer.
As part of our focus on cancer, Merck is committed to exploring the potential of immuno-oncology with one of the fastest-growing development programs in the industry. We are currently executing an expansive research program that includes more than 270 clinical trials evaluating our anti-PD-1 therapy across more than 30 tumor types. We also continue to strengthen our immuno-oncology portfolio through strategic acquisitions and are prioritizing the development of several promising immunotherapeutic candidates with the potential to improve the treatment of advanced cancers.
For more information about our oncology clinical trials, visit www.merck.com/clinicaltrials .
For 125 years, Merck has been a global health care leader working to help the world be well. Merck is known as MSD outside the United States and Canada. 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. For more information, visit www.merck.com  and connect with us on Twitter , Facebook , YouTube  and LinkedIn .
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