An experimental cholesterol drug developed by Sanofi and Regeneron is also effective in lowering the amount of bad cholesterol in the body by 30 percent even if taken once a month instead of the original two-week interval.

The first trial of Alirocumab involved 803 patients with hypercholesterolemia, or excessive cholesterol in the blood, who also have moderate cardiovascular risk. They were given 300 mg of alirocumab every four weeks and their progress was compared to 300 patients who received placebo and statin therapy.

The second trial involved 233 patients with hypercholesterolemia, high cardiovascular risk and have undergone statin therapy prior to the study. They received only 150 mg of alirocumab every four weeks and their data was compared to another placebo group who didn't receive statin therapy.

Some of the side effects noted in the clinical trials include headache, upper respiratory tract infection, nausea, joint pain, sinusitis and fatigue. But the number of people affected was only five percent.

After the 12-week study period, the researchers found that those who received 300mg of the drug every four weeks lowered their cholesterol levels by 30 percent compared to the placebo group.

"These results continue to validate our clinical development approach, which is designed to investigate various alirocumab doses and intervals to address patients' lipid-lowering needs," said Bill Sasiela, Ph.D., Vice President, Program Direction, Cardiovascular and Metabolic, Regeneron in a press release.

Alirocumab is expected to reduce the number of heart attacks and strokes of patients by 50 percent by decreasing the amount of bad cholesterol in the body. Several clinical trials were launched to test the efficiency of the drug and all trials are expected to be completed early this year.

Roth Capital's Joseph Pantginis told Reuters that the drug will lead to billions of revenues for Sanofi and Regeneron as about 36 million Americans are eligible for the drug by 2016.

Both have not revealed the pricing of the drug yet, but Barclays analysts estimated last year that a therapy using this drug may cost $6,000 per year.