This study examined the mutation status of the K-ras gene in colorectal tumors from patients who were enrolled in a trial of cetuximab, a monoclonal antibody against the epidermal growth factor receptor (EGFR). A survival benefit was found among patients with tumors bearing wild-type K-ras but not among patients with tumors bearing mutated K-ras. Wild-type K-ras is essential in transmitting signals initiated by EGFR.

Toll-like receptors (TLRs) are a central aspect of the innate immune response. Different TLRs are associated with the immune response to different infectious pathogens. In this retrospective analysis, an increased susceptibility to invasive aspergillosis was associated with certain polymorphisms in donor TLR4 in patients who received an allogeneic hematopoietic stem-cell transplant from an unrelated donor.

In patients with symptomatic atrial fibrillation and heart failure, pulmonary-vein isolation was found to be superior to atrioventricular-node ablation with biventricular pacing. Isolation of the pulmonary veins by means of ablation is a viable option for patients with refractory atrial fibrillation and heart failure.

In this randomized, phase 2 trial involving previously untreated patients with early, relapsing–remitting multiple sclerosis, alemtuzumab, a monoclonal antibody targeting CD52 on lymphocytes and monocytes, was more effective than interferon beta-1a in reducing the progression of disability and relapse. Alemtuzumab caused autoimmune complications, including immune thrombocytopenic purpura (resulting in one death) and thyroid disorders.