6.1Clinical Studies Experience
Because clinical studies are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in clinical studies of another drug and may not reflect the rates observed in practice. Primary Hyperlipidemia In 7 double-blind, placebo-controlled clinical trials, 807 patients with primary hyperlipidemia (age range 18 years to 86 years, 50% women, 90% Caucasians, 7% Blacks, 2% Hispanics, 1% Asians) and elevated LDL-C were treated with colesevelam hydrochloride 1.5 g/day to 4.5 g/day from 4 weeks to 24 weeks (total exposure 199 patient-years).
Table 1 Clinical Studies of Colesevelam Hydrochloride for Primary Hyperlipidemia: Adverse Reactions Reported in ≥ 2% of Patients and More Commonly than in Placebo Colesevelam Hydrochloride N = 807 Placebo N = 258 Constipation 11% 7% Dyspepsia 8.3% 3.5% Nausea 4.2% 3.9% Accidental injury 3.7% 2.7% Asthenia 3.6% 1.9% Pharyngitis 3.2% 1.9% Flu syndrome 3.2% 3.1% Rhinitis 3.2% 3.1% Myalgia 2.1% 0.4% Pediatric Patients 10 Years to 17 Years of Age In an 8-week double-blind, placebo-controlled study, boys and post-menarchal girls, 10 years to 17 years of age, with HeFH (n = 194), were treated with colesevelam hydrochloride tablets (1.9 g to 3.8 g, daily) or placebo tablets.
Table 2 Clinical Study of Colesevelam Hydrochloride for Primary Hyperlipidemia in HeFH Pediatric Patients: Adverse Reactions Reported in ≥ 2% of Patients and More Commonly than in Placebo Colesevelam Hydrochloride N = 129 Placebo N = 65 Nasopharyngitis 6.2% 4.6% Headache 3.9% 3.1% Fatigue 3.9% 1.5% Creatine Phosphokinase Increase 2.3% 0% Rhinitis 2.3% 0% Vomiting 2.3% 1.5% The reported adverse reactions during the additional 18-week open-label treatment period with colesevelam hydrochloride 3.8 g per day were similar to those during the double-blind period and included headache (7.6%), nasopharyngitis (5.4%), upper respiratory tract infection (4.9%), influenza (3.8%), and nausea (3.8%).
Type 2 Diabetes Mellitus In 5 add-on combination and 1 monotherapy double-blind, 12- to 26-week, placebo-controlled clinical trials in patients with type 2 diabetes mellitus, 1022 patients were treated with colesevelam hydrochloride. The mean exposure duration was 20 weeks (total exposure 393 patient-years). Patients were to receive 3.8 grams of colesevelam hydrochloride per day. The mean age of patients was 55.7 years, 52.8 percent of the population was male and 61.9% were Caucasian, 4.8% were Asian, and 15.9% were Black or African American.
At baseline the population had a mean hemoglobin A1c (HbA1c) of 8.2%, and 26% had past medical history suggestive of microvascular complications of diabetes. Table 3 shows adverse reactions associated with the use of colesevelam hydrochloride in patients with type 2 diabetes. These adverse reactions were not present at baseline, occurred more commonly on colesevelam hydrochloride than on placebo, and occurred in at least 2% of patients treated with colesevelam hydrochloride.
Table 3 Clinical Studies of Colesevelam Hydrochloride for Type 2 Diabetes: Adverse Reactions Reported in ≥ 2% of Patients and More Commonly than in Placebo Colesevelam Hydrochloride N = 1,022 Placebo N = 1,010 Constipation 6.5% 2.2% Hypoglycemia 3.4% 3.1% Dyspepsia 2.8% 1.0% Nausea 2.6% 1.6% Hypertension 2.6% 1.9% Back Pain 2.3% 1.3% A total of 5.3% of colesevelam hydrochloride-treated patients and 3.6% of placebo-treated patients were discontinued from the diabetes trials due to adverse reactions.
This difference was driven mostly by gastrointestinal adverse reactions such as abdominal pain and constipation. One patient in the add-on to sulfonylurea trial discontinued due to body rash and mouth blistering that occurred on the first day of dosing of colesevelam hydrochloride, which may represent a hypersensitivity reaction to colesevelam hydrochloride. Hypertriglyceridemia Patients with fasting serum TG levels above 500 mg/dL were excluded from the diabetes clinical trials.
In the diabetes trials, 1,292 (67.7%) patients had baseline fasting serum TG levels less than 200 mg/dL, 426 (22.3%) had baseline fasting serum TG levels between 200 and less than 300 mg/dL, 175 (9.2%) had baseline fasting serum TG levels between 300 mg/dL and 500 mg/dL, and 16 (0.8%) had fasting serum TG levels greater than or equal to 500 mg/dL. The median baseline fasting TG concentration for the study population was 160 mg/dL; the median post-treatment fasting TG was 180 mg/dL in the colesevelam hydrochloride group and 162 mg/dL in the placebo group.
Colesevelam hydrochloride therapy resulted in a median placebo-corrected increase in serum TG of 9.7% (p = 0.03) in the monotherapy study and of 5% (p = 0.22), 11% (p < 0.001), 18% (p < 0.001), and 22% (p < 0.001), when added to metformin, pioglitazone, sulfonylureas, and insulin, respectively. In comparison, colesevelam hydrochloride resulted in a median increase in serum TG of 5% compared to placebo (p = 0.42) in a 24-week monotherapy lipid-lowering trial.
Fasting TG concentrations ≥ 500 mg/dL occurred in 0.9% of colesevelam hydrochloride-treated patients compared to 0.7% of placebo‑treated patients in the diabetes trials. Among these patients, the TG concentrations with colesevelam hydrochloride (median 606 mg/dL; interquartile range 570 mg/dL to 794 mg/dL) were similar to that observed with placebo (median 663 mg/dL; interquartile range 542 mg/dL to 984 mg/dL). Five (0.6%) patients on colesevelam hydrochloride and 3 (0.3%) patients on placebo developed TG elevations > 1,000 mg/dL.
Cardiovascular Adverse Reactions During the diabetes trials, the incidence of patients with serious adverse reactions involving the cardiovascular system was 2.2% (22/1,022) in the colesevelam hydrochloride group and 1% (10/1,010) in the placebo group. These overall rates included disparate events (e.g., myocardial infarction, aortic stenosis, and bradycardia); therefore, the significance of this imbalance is unknown.
