The most common adverse events observed in the study (observed in greater than 20% of patients) included muscle spasms, hair loss, altered taste sensation, weight loss, fatigue, nausea, decreased appetite, and diarrhea. Serious adverse events (SAEs) were observed in 26 patients (25 percent). Four of these patients (4 percent) had SAEs that were considered to be possibly related to vismodegib, including one case each of: blocked bile flow from the liver (cholestasis), dehydration with loss of consciousness (syncope), pneumonia accompanied by an inability of the heart to pump enough blood (cardiac failure) and a sudden arterial blockage in the lung (pulmonary embolism). Fatal events were reported in seven patients (7 percent); none were considered by investigators to be related to vismodegib. In all fatalities, pre-existing risk factors and comorbid conditions were present.About Basal Cell Carcinoma BCC is the most common cancer in the United States and the most common type of skin cancer, accounting for approximately two million new cases annually. The disease is generally considered curable when the cancer is restricted to a small area of the skin. However, in a small group of people, if the disease is left untreated or does not respond to treatment, the cancer may advance further into the skin, bones or other tissues, or spread to other parts of the body. In such rare cases, the disease can become difficult to treat and life-threatening. There are no approved therapies to treat advanced basal cell carcinoma. About Vismodegib and the Hedgehog Pathway Vismodegib is designed to selectively inhibit signaling in the Hedgehog pathway by targeting a protein called Smoothened. The Hedgehog signaling pathway plays an important role in regulating proper growth and development in the early stages of life and becomes less active in adults. However, mutations in the pathway that reactivate Hedgehog signaling are seen in several different types of cancer. Abnormal signaling in the Hedgehog pathway is implicated in the more than 90 percent of BCC cases.