On March 24, 2016 Astellas Pharma Inc. (TSE: 4503) and Medivation, Inc. (NASDAQ: MDVN) reported that the ARCHES (AR Inhibition with ChemoHormonal Therapy in Men with MEtastatic Castrate Sensitive Prostate Cancer) Phase III registrational trial, which will evaluate the efficacy and safety of enzalutamide with androgen deprivation therapy (ADT) versus placebo with ADT in metastatic hormone sensitive prostate cancer (mHSPC) patients, has been initiated and the first patient has been randomized (Press release, Astellas, MAR 24, 2016, View Source [SID:1234509946]).

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

Prostate cancer is the most commonly diagnosed cancer and the second-leading cause of cancer death in men in the United States. According to the American Cancer Society, approximately 181,000 new cases of prostate cancer will be diagnosed, and 26,000 men will die of prostate cancer in the United States in 2016.i Androgen deprivation therapy, which reduces the levels of androgens (male hormones), is the standard of care for patients with mHSPC. The ARCHES trial will investigate whether the addition of enzalutamide to ADT may benefit this patient population compared to ADT alone.

"Dosing of the first patient in this trial demonstrates our ongoing commitment to continuing to investigate enzalutamide," said Claire Thom, Pharm D., senior vice president and oncology therapeutic area head, Astellas.

"This trial targets an important patient population as we advance the development of enzalutamide," said Mohammad Hirmand, M.D., interim chief medical officer, Medivation. "The initiation of this trial demonstrates our ongoing commitment to fully develop enzalutamide in this serious disease."

The global, Phase III, randomized, double-blind, placebo-controlled study, which is being led by Astellas, will evaluate the efficacy and safety of enzalutamide with ADT versus placebo with ADT in patients with mHSPC. ARCHES will enroll approximately 1,100 patients with mHSPC at approximately 250 centers globally. The 2 primary endpoint of the trial is radiographic progression-free survival (rPFS), defined as the time from randomization to the first objective evidence of radiographic disease progression as assessed by central review or death, whichever occurs first. The trial will evaluate enzalutamide at a dose of 160 mg to be taken orally once daily versus placebo, administered with ADT.

For more information about this trial, visit www.clinicaltrials.gov, trial identifier NCT02677896.

Enzalutamide is being developed through a collaboration between Astellas and Medivation. Enzalutamide, which is known by the brand name XTANDI, is not approved for use in patients with metastatic hormone sensitive prostate cancer (mHSPC).

About XTANDI XTANDI (enzalutamide) capsules is an androgen receptor inhibitor that blocks multiple steps in the androgen receptor signaling pathway within the tumor cell. In preclinical studies, enzalutamide has been shown to competitively inhibit androgen binding to androgen receptors, and inhibit androgen receptor nuclear translocation and interaction with DNA. The clinical significance of this MOA is unknown. XTANDI is approved by the U.S. Food and Drug Administration for the treatment of patients with metastatic castration-resistant prostate cancer (CRPC).

Important Safety Information

Contraindications XTANDI is not indicated for women and is contraindicated in women who are or may become pregnant. XTANDI can cause fetal harm when administered to a pregnant woman.

Warnings and Precautions

Seizure In Study 1, conducted in patients with metastatic castration-resistant prostate cancer (CRPC) who previously received docetaxel, seizure occurred in 0.9% of XTANDI patients and 0% of placebo patients. In Study 2, conducted in patients with chemotherapy-naive metastatic CRPC, seizure occurred in 0.1% of XTANDI patients and 0.1% of placebo patients. There is no clinical trial experience re- administering XTANDI to patients who experienced a seizure, and limited safety data are available in patients with predisposing factors for seizure. Study 1 excluded the use of concomitant medications that may lower threshold; Study 2 permitted the use of these medications. Because of the risk of seizure associated with XTANDI use, patients should be advised of the risk of engaging in any activity during which sudden loss of consciousness could cause serious harm to themselves or others. Permanently discontinue XTANDI in patients who develop a seizure during treatment.

Posterior Reversible Encephalopathy Syndrome (PRES) In post approval use, there have been reports of PRES in patients receiving XTANDI. PRES is a neurological disorder which can present with rapidly evolving symptoms including seizure, headache, lethargy, confusion, blindness, and other visual and neurological disturbances, with or without associated hypertension. A diagnosis of PRES requires confirmation by brain imaging, preferably MRI. Discontinue XTANDI in patients who develop PRES.

Adverse Reactions

The most common adverse reactions (≥ 10%) reported from two combined clinical studies that occurred more commonly (≥ 2% over placebo) in XTANDI patients were asthenia/fatigue, back pain, decreased appetite, constipation, arthralgia, diarrhea, hot flush, upper respiratory tract infection, peripheral edema, dyspnea, musculoskeletal pain, weight decreased, headache, hypertension, and dizziness/vertigo.

In Study 1, Grade 3 and higher adverse reactions were reported among 47% of XTANDI patients and 53% of placebo patients. Discontinuations due to adverse events were reported for 16% of XTANDI patients and 18% of placebo patients. In Study 2, Grade 3-4 adverse reactions were reported in 44% of XTANDI patients and 37% of placebo patients. Discontinuations due to adverse events were reported for 6% of both study groups.

Lab Abnormalities: Grade 1-4 neutropenia occurred in 15% of XTANDI patients (1% Grade 3-4) and 6% of placebo patients (0.5% Grade 3-4). Grade 1-4 thrombocytopenia occurred in 6% of XTANDI patients (0.3% Grade 3-4) and 5% of placebo patients (0.5% Grade 3-4). Grade 1-4 elevations in ALT occurred in 10% of 3 XTANDI patients (0.2% Grade 3-4) and 16% of placebo patients (0.2% Grade 3-4). Grade 1-4 elevations in bilirubin occurred in 3% of XTANDI patients (0.1% Grade 3-4) and 2% of placebo patients (no Grade 3-4).

Infections: In Study 1, 1% of XTANDI patients compared to 0.3% of placebo patients died from infections or sepsis. In Study 2, 1 patient in each treatment group (0.1%) had an infection resulting in death.

Falls (including fall-related injuries), occurred in 9% of XTANDI patients and 4% of placebo patients. Falls were not associated with loss of consciousness or seizure. Fall-related injuries were more severe in XTANDI patients, and included non-pathologic fractures, joint injuries, and hematomas.

Hypertension occurred in 11% of XTANDI patients and 4% of placebo patients. No patients experienced hypertensive crisis. Medical history of hypertension was balanced between arms. Hypertension led to study discontinuation in < 1% of all patients.

Drug Interactions

Effect of Other Drugs on XTANDI Avoid strong CYP2C8 inhibitors, as they can increase the plasma exposure to XTANDI. If co-administration is necessary, reduce the dose of XTANDI. Avoid strong CYP3A4 inducers as they can decrease the plasma exposure to XTANDI. If co-administration is necessary, increase the dose of XTANDI.

Effect of XTANDI on Other Drugs Avoid CYP3A4, CYP2C9, and CYP2C19 substrates with a narrow therapeutic index, as XTANDI may decrease the plasma exposures of these drugs. If XTANDI is coadministered with warfarin (CYP2C9 substrate), conduct additional INR monitoring.

For Full Prescribing Information for XTANDI (enzalutamide) capsules, please visit View Source

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1‐800‐FDA‐1088.