Clinical Trials Experience
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The adverse reaction information from clinical trials does, however, provide a basis for identifying the adverse events that appear to be related to drug use and for approximating rates.
Amlodipine besylate and benazepril hydrochloride has been evaluated for safety in over 2,991 patients with hypertension; over 500 of these patients were treated for at least 6 months, and over 400 were treated for more than 1 year.
In a pooled analysis of 5 placebo-controlled trials involving amlodipine besylate and benazepril hydrochloride doses up to 5/20, the reported side effects were generally mild and transient, and there was no relationship between side effects and age, sex, race, or duration of therapy. Discontinuation of therapy due to side effects was required in approximately 4% of patients treated with amlodipine besylate and benazepril hydrochloride and in 3% of patients treated with placebo.
The most common reasons for discontinuation of therapy with amlodipine besylate and benazepril hydrochloride in these studies were cough and edema (including angioedema).
The peripheral edema associated with amlodipine use is dose-dependent. When benazepril is added to a regimen of amlodipine, the incidence of edema is substantially reduced.
The addition of benazepril to a regimen of amlodipine should not be expected to provide additional antihypertensive effect in African-Americans. However, all patient groups benefit from the reduction in amlodipine-induced edema.
The side effects considered possibly or probably related to study drug that occurred in these trials in more than 1% of patients treated with amlodipine besylate and benazepril hydrochloride are shown in the table below. Cough was the only adverse event with at least possible relationship to treatment that was more common on amlodipine besylate and benazepril hydrochloride (3.3%) than on placebo (0.2%).
PERCENT INCIDENCE IN U.S. PLACEBO-CONTROLLED TRIALS
*Edema refers to all edema, such as dependent edema, angioedema, facial edema.
The incidence of edema was greater in patients treated with amlodipine monotherapy (5.1%) than in patients treated with amlodipine besylate and benazepril hydrochloride (2.1%) or placebo (2.2%).
Other side effects considered possibly or probably related to study drug that occurred in U.S. placebo-controlled trials of patients treated with amlodipine besylate and benazepril hydrochloride or in postmarketing experience were the following:
Body as a Whole: Asthenia and fatigue.
CNS: Insomnia, nervousness, anxiety, tremor, and decreased libido.
Dermatologic: Flushing, hot flashes, rash, skin nodule, and dermatitis.
Digestive: Dry mouth, nausea, abdominal pain, constipation, diarrhea, dyspepsia, and esophagitis.
Metabolic and Nutritional: Hypokalemia.
Musculoskeletal: Back pain, musculoskeletal pain, cramps, and muscle cramps.
Urogenital: Sexual problems such as impotence, and polyuria.
Monotherapies of benazepril and amlodipine have been evaluated for safety in clinical trials in over 6,000 and 11,000 patients, respectively. The observed adverse reactions to the monotherapies in these trials were similar to those seen in trials of amlodipine besylate and benazepril hydrochloride.
Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
In postmarketing experience with benazepril, there have been rare reports of Stevens-Johnson syndrome, pancreatitis, hemolytic anemia, pemphigus, and thrombocytopenia. Jaundice and hepatic enzyme elevations (mostly consistent with cholestasis) severe enough to require hospitalization have been reported in association with use of amlodipine. Other potentially important adverse experiences attributed to other ACE inhibitors and calcium channel blockers include: eosinophilic pneumonitis (ACE inhibitors) and gynecomastia (CCBs). Other infrequently reported events included chest pain, ventricular extrasystole, gout, neuritis, tinnitus, alopecia, upper respiratory tract infection, palpitations and somnolence.