Clinical Trials

Cancer Outcomes Improved with Panitumumab and Chemotherapy

The results of a recent phase 3 study showed that panitumumab (Vectibix), administered in combination with FOLFOX (an oxaliplatin-based chemotherapy), significantly prolonged progression-free survival (PFS), compared with FOLFOX alone in the first-line treatment of patients with KRAS wild-type metastatic colorectal cancer (mCRC). Approved in the United States in September 2006, panitumumab is a human anti—epidermal growth factor receptor indicated for the treatment of mCRC. The study, known as Panitumumab Randomized Trial in Combination with Chemotherapy for Metastatic Colorectal Cancer to Determine Efficacy (PRIME), enrolled 1183 patients globally who were randomized to receive either 6.0 mg/kg of panitumumab and FOLFOX4 once every 2 weeks or FOLFOX alone every 2 weeks. The primary end point was PFS by KRAS status. Tumor KRAS was ascertained in more than 90% of the 1183 patients enrolled in PRIME. In patients with tumors harboring activating KRAS mutations, PFS was significantly inferior in the panitumumab arm. By determining KRAS status, the appropriate patient population in which to treat with panitumumab can more easily be identified.

Investigational Drug in New Class Shows Positive Results with SLE

Belimumab (Benlysta) recently met the primary end point in 1 of 2 phase 3 trials, BLISS-52, in patients with serologically active systemic lupus erythematosus (SLE). Belimumab is an investigational drug and the first in a new class of drugs called BLySspecific inhibitors. No new drug has been approved for SLE in more than 50 years. The placebo-controlled study results showed that belimumab plus standard of care achieved a clinically and statistically significant improvement in patient response rate at week 52, compared with standard of care alone. The drug was also well-tolerated during the study.

CNS Stimulant Improves ADHD Symptoms

A study, recently published online in Child Adolescent Psychiatry and Mental Health, found lisdexamfetamine dimesylate (Vyvanse) CII, a central nervous system (CNS) stimulant, significantly reduced the symptoms of attention- deficit/hyperactivity disorder (ADHD) in children aged 6 to 12 from the first time point measured (1.5 hours) up to the last time point assessed (13 hours) after administration. The study, a randomized, double-blind, placebocontrolled, analog classroom study, included 129 children aged 6 to 12 years with ADHD.

The primary objective of this study was to assess the time of onset of lisdexamfetamine dimesylate, compared with placebo, as measured by the Swanson, Kotkin, Agler, M-Flynn, and Pelham Deportment rating scale. Lisdexamfetamine dimesylate showed significant efficacy versus placebo at 1.5 hours; in addition, the drug was associated with significant efficacy as measured by both subjective and objective assessments from the first time point through the last time point assessed during the classroom day, and at all time points in between. The prescribing information was updated to reflect this efficacy at 13 hours after administration for pediatric patients.

Longer Antiviral Treatment Protects Better Against Cytomegalovirus Disease

Results from the Improved Protection Against Cytomegalovirus (CMV) in Transplant (IMPACT) trial, a phase 3 study, were presented recently at the ninth annual American Transplant Congress 2009. The data showed that doubling the duration of preventive therapy (prophylaxis) with oral valganciclovir (Valcyte) significantly reduced the incidence of CMV disease by 56% in high-risk kidney transplant patients within the first year posttransplant. CMV is a major cause of morbidity and mortality during the first 6 months after transplantation and is of concern for transplant recipients. The IMPACT trial was a global, multicenter, double-blind study that randomized 326 high-risk kidney allograft recipients to 1 of 2 treatment groups: (1) 100 days valganciclovir (900 mg once daily) posttransplant followed by 100 days placebo; or (2) 200 days valganciclovir (900 mg once daily) posttransplant. Researchers found that 200-day valganciclovir treatment prevented CMV disease in 84% of patients and significantly reduced the incidence of CMV disease by 56%, compared with the current standard therapy—100-day valganciclovir treatment (P <.00001). No significant difference was detected in overall safety and tolerability, demonstrating that extended treatment poses no additional risk to patients.