New FDA Approvals
These drugs recently received final approval from the U.S. Food and Drug Administration (FDA):
• Enfuvirtide (Fuzeon) by Roche Pharmaceuticals. The FDA has announced the accelerated approval of enfuvirtide (Fuzeon) for use in combination with other anti-HIV medications to treat advanced HIV-1 infection in adults and children ages 6 years and older.
The announcement makes enfuvirtide the first product in a new class of medications called fusion inhibitors to receive marketing approval anywhere in the world. Drugs in this class interfere with the entry of HIV-1 into cells by inhibiting the fusion of viral and cellular membranes. This inhibition blocks the virus’ ability to infect certain components of the immune system.
Enfuvirtide can be used as part of a medication regimen in patients for whom there are limited options. Enfuvirtide should only be used in patients who have previously used other anti-HIV medications and have ongoing evidence of viral replication. The drug is administered as a twice-daily subcutaneous injection.
The approved labeling for enfuvirtide warns physicians to monitor patients carefully for signs and symptoms of pneumonia. Although bacterial pneumonia was uncommon in clinical study participants, more patients treated with the drug developed bacterial pneumonia than did patients who did not receive it. In addition, enfuvirtide can cause both serious systemic allergic reactions and local skin reactions at the site of injection.
The long-term effects of enfuvirtide are not known at this time but are being evaluated by the ongoing clinical studies. The drug is expected to cost about $20,000 a year.
• Lower-dose single tablet of a combination estrogen and progestin drug (Prempro) by Wyeth Pharmaceuticals. The FDA has approved a lower-dose single tablet of Prempro, containing 0.45 estrogen and 1.5 progestin (medroxyprogesterone), to treat specific symptoms of menopause. The lower dose provides favorable tolerability and an efficacy profile comparable to the most frequently prescribed strength of Prempro, with 28% less estrogen and 40% less progestin.
The drug is effective for treating moderate-to-severe symptoms of hot flashes and night sweats and is indicated for the treatment of moderate-to-severe symptoms of vulvar and vaginal atrophy. However, topical vaginal products should be considered when being prescribed solely for the treatment of symptoms of vulvar and vaginal atrophy.
The new lower dose will provide an additional option for postmenopausal women. The FDA continues to advise women to talk to their doctors and, if they decide that estrogen and progestin combination products are appropriate, they should use the lowest dose for the shortest duration to reach treatment goals.
The FDA reminds women that estrogens and progestins should not be used to prevent heart disease, heart attacks, or strokes.
• Aprepitant (Emend) by Merck & Co. The FDA has approved aprepitant (Emend) to be used in combination with other anti-nausea and anti-vomiting drugs for prevention of acute and delayed nausea and vomiting associated with initial and repeat courses of chemotherapy known to cause these problems, including high-dose cisplatin.
Aprepitant is the first FDA-approved treatment that prevents the delayed nausea and vomiting symptoms that many patients experience more than 24 hours after receiving chemotherapy. Aprepitant is part of a three-drug therapy that works with other drugs to treat nausea and vomiting. It reduces nausea and vomiting in a new way by blocking receptors in the brain called NK1 receptors.
Aprepitant may interact with some drugs, including some chemotherapies, birth control pills, blood thinners, and other drugs. Aprepitant also may reduce the effectiveness of oral contraceptives.
Patients being treated with blood thinners such as warfarin will need to have their blood tested after the completion of a three-day regimen that includes aprepitant with each chemotherapy cycle to determine whether the dose of the blood-thinning medicine needs to be changed.
• Propranolol hydrochloride (InnoPran XL) by Reliant Pharmaceuticals, LLC. The FDA has approved propranolol hydrochloride (InnoPran XL), a bedtime-dosed, extended-release formulation of propranolol hydrochloride, for the treatment of hypertension.
Propranolol hydrochloride provides 24-hour blood pressure control in a once-daily formulation and a dosing range from 80 mg to 120 mg. It is the only product in its class approved for administration in the evening. Propranolol hydrochloride can be used alone or in combination with other anti-hypertensive agents. With evening administration, clinical trials have shown reduction in blood pressure in the early morning hours and sustained control throughout the day.
The most commonly reported side effects were fatigue, dizziness, and constipation. Propranolol hydrochloride is contraindicated in cardiogenic shock, sinus bradycardia, and greater than first-degree block bronchial asthma, and in patients with known hypersensitivity to propranolol hydrochloride.
Propranolol hydrochloride will be available in 80 mg and 120 mg capsules.
• Pegvisomant for injection (Somavert) by Pharmacia Corp. The FDA has approved pegvisomant (Somavert) for the treatment of acromegaly. The drug is approved for patients who have had an inadequate response to existing therapies.
Pegvisomant, the first in a new class of drugs called growth hormone receptor antagonists, normalized concentrations of IGF-I in more than 90% of patients by blocking the effects of growth hormone.
Acromegaly causes headaches, profuse sweating, swelling, joint disorders, changes in facial features, and enlarged hands, feet, and jaw. If untreated, patients with acromegaly often have a shortened life span because of heart and respiratory diseases, diabetes mellitus, and cancer.
In clinical studies, the most commonly reported side effects of pegvisomant use were injection site reactions, sweating, headache, and fatigue. Patients should have tests to monitor their liver function during the first six months of therapy with pegvisomant. The drug also is contraindicated in patients with hypersensitivity to any of its components. The stopper on the vial contains latex.
• New indication for infliximab (Remicade) by Centocor. The FDA has granted marketing approval for infliximab (Remicade) for reducing the number of draining enterocutaneous and rectovaginal fistulas and for maintaining fistula closure in patients with fistulizing Crohn’s disease. The new maintenance indication requires treatment every eight weeks, following an induction regimen in which patients receive doses at weeks 0, 2, and 6. Infliximab, a tumor necrosis factor-alpha therapy, is the only biologic drug indicated for the treatment of both Crohn’s disease and rheumatoid arthritis.
In June 2002, the FDA approved infliximab for use in inducing and maintaining clinical remission in patients with moderate-to-severe Crohn’s disease using maintenance dosing every eight weeks.