In April 2012, the US Food and Drug Administration approved Stendra, a new medication for erectile dysfunction. An estimated 30 million American men are affected by erectile dysfunction, according to the FDA.
Stendra (avanafil joins Viagra, Cialis and Levitra, all from a class of drugs known as phosphodiesterase type 5 inhibitors that help boost blood flow to the penis.
According to the FDA, fast-acting Stendra is designed to be taken 30 minutes before sexual activity and at the lowest effective dose.
Stendra's safety and efficacy were established in three double-blind, placebo-controlled clinical studies. A total of 1,267 patients were randomly assigned to take Stendra for up to 12 weeks at doses of 50 milligrams (mg), 100 mg or 200 mg, or a placebo as needed about 30 minutes before sexual activity.
Stendra is marketed by Vivus Inc., based in Mountain View, California.
Whether the new drug adds any value to the existing range of impotence medications is unclear, one expert said.
Bruce Kava, MD, acting chairman of urology at the University of Miami School of Medicine, said "the only advantage Stendra may have is a more rapid onset of action over the other drugs. The question is whether there are any advantages to a more rapid onset."
He noted that often patients don't respond to any brand of erectile dysfunction drugs. And there is currently no way of telling who will respond to which drug, "Sometimes it's hit or miss," he explained.
Men will have to try each individual brand to find the one that best suits their lifestyle, Dr. Kava said. For example, for some men Cialis works best because its effects seem to last much longer than that of the other drugs, he said.
The FDA said Stendra's approval means one more option for patients.
"This approval expands the available treatment options to men experiencing erectile dysfunction, and enables patients, in consultation with their doctor, to choose the most appropriate treatment for their needs," Victoria Kusiak, MD, deputy director of the Office of Drug Evaluation III in the FDA's Center for Drug Evaluation and Research, said in a recent FDA news release.
Side Effects And Warnings
Stendra comes with the same warnings as its companions in this drug class. It should not be taken by men who take nitrates-drugs used to treat chest pain (angina). This combination can cause a sudden drop in blood pressure, the FDA cautioned.
The agency also warned that these drugs can, in rare cases, cause color vision changes and in a few instances, men have also reported a sudden loss of vision in one or both eyes. Sudden loss or decrease in hearing has also been reported in patients taking these drugs. "Patients who experience a sudden loss of vision or hearing should stop taking PDE5 inhibitors, including Stendra, and call a doctor right away," the FDA said.
The most common side effects reported with Stendra include headache, redness of the face and other areas, nasal congestion, cold-like symptoms and back pain.
Also in rare cases, patients taking these drugs may get an erection lasting four hours indefinitely. "If this happens, patients should seek immediate medical care," the agency said.
Testosterone Does Not Help Erectile Dysfunction
Recent research found that replacing testosterone in men who had borderline low levels of the hormone did not improve the men's ability to achieve and maintain erections. Men with ED should discuss treatment options with their physicians.