Welchol (Page 4 of 6)

13 NONCLINICAL TOXICOLOGY

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

Carcinogenesis

A 104-week carcinogenicity study with colesevelam hydrochloride was conducted in CD-1 mice, at oral dietary doses up to 3 g/kg/day. This dose was approximately 50 times the maximum recommended human dose of 4.5 g/day, based on body weight, mg/kg. There were no significant drug-induced tumor findings in male or female mice. In a 104-week carcinogenicity study with colesevelam hydrochloride in Harlan Sprague-Dawley rats, a statistically significant increase in the incidence of pancreatic acinar cell adenoma was seen in male rats at doses >1.2 g/kg/day (approximately 20 times the maximum human dose, based on body weight, mg/kg) (trend test only). A statistically significant increase in thyroid C-cell adenoma was seen in female rats at 2.4 g/kg/day (approximately 40 times the maximum human dose, based on body weight, mg/kg).

Mutagenesis

Colesevelam hydrochloride and 4 degradants present in the drug substance have been evaluated for mutagenicity in the Ames test and a mammalian chromosomal aberration test. The 4 degradants and an extract of the parent compound did not exhibit genetic toxicity in an in vitro bacterial mutagenesis assay in S. typhimurium and E. coli (Ames assay) with or without rat liver metabolic activation. An extract of the parent compound was positive in the Chinese Hamster Ovary (CHO) cell chromosomal aberration assay in the presence of metabolic activation and negative in the absence of metabolic activation. The results of the CHO cell chromosomal aberration assay with 2 of the 4 degradants, decylamine HCl and aminohexyltrimethyl ammonium chloride HCl, were equivocal in the absence of metabolic activation and negative in the presence of metabolic activation. The other 2 degradants, didecylamine HCl and 6-decylamino-hexyltrimethyl ammonium chloride HCl, were negative in the presence and absence of metabolic activation.

Impairment of Fertility

Colesevelam hydrochloride did not impair fertility in rats at doses up to 3 g/kg/day (approximately 50 times the maximum human dose, based on body weight, mg/kg).

13.2 Animal Toxicology and/or Pharmacology

Reproductive Toxicology Studies

Reproduction studies have been performed in rats and rabbits at doses up to 3 g/kg/day and 1 g/kg/day, respectively (approximately 50 and 17 times the maximum human dose, based on body weight, mg/kg) and have revealed no evidence of harm to the fetus due to colesevelam hydrochloride.

14 CLINICAL STUDIES

14.1 Primary Hyperlipidemia

WELCHOL reduces total cholesterol (TC), LDL-C, apolipoprotein B (Apo B), and non-high-density lipoprotein cholesterol (non-HDL-C) when administered alone or in combination with a statin in patients with primary hyperlipidemia.

Approximately 1600 patients were studied in 9 clinical trials with treatment durations ranging from 4 to 50 weeks. With the exception of one open-label, uncontrolled, long-term extension study, all studies were multicenter, randomized, double-blind, and placebo-controlled. A maximum therapeutic response to WELCHOL was achieved within 2 weeks and was maintained during long-term therapy.

Monotherapy

In a study in patients with LDL-C between 130 mg/dL and 220 mg/dL (mean 158 mg/dL), WELCHOL was given for 24 weeks in divided doses with the morning and evening meals.

As shown in Table 7, the mean LDL-C reductions were 15% and 18% at the 3.8 g and 4.5 g doses. The respective mean TC reductions were 7% and 10%. The mean Apo B reductions were 12% in both treatment groups. WELCHOL at both doses increased HDL-C by 3%. Increases in TG of 9-10% were observed at both WELCHOL doses, but the changes were not statistically different from placebo.

Table 7 Response to WELCHOL Monotherapy in a 24-Week Trial — Percent Change in Lipid Parameters from Baseline
Grams/Day N TC LDL-C Apo B HDL-C * Non-HDL-C TG *
*
Median % change from baseline
p<0.05 for lipid parameters compared to placebo, for Apo B compared to baseline
Placebo 88 +1 0 0 −1 +1 +5
3.8 g (6 tablets) 95 −7 −15 −12 +3 −10 +10
4.5 g (7 tablets) 94 −10 −18 −12 +3 −13 +9

In a study in 98 patients with LDL-C between 145 mg/dL and 250 mg/dL (mean 169 mg/dL), WELCHOL 3.8 g was given for 6 weeks as a single dose with breakfast, as a single dose with dinner, or as divided doses with breakfast and dinner. The mean LDL-C reductions were 18%, 15%, and 18% for the 3 dosing regimens, respectively. The reductions with these 3 regimens were not statistically different from one another.

Combination Therapy

Co-administration of WELCHOL and a statin (atorvastatin, lovastatin, or simvastatin) in 3 clinical studies demonstrated an additive reduction of LDL-C. The mean baseline LDL-C was 184 mg/dL in the atorvastatin study (range 156-236 mg/dL), 171 mg/dL in the lovastatin study (range 115-247 mg/dL), and 188 mg/dL in the simvastatin study (range 148-352 mg/dL). As demonstrated in Table 8, WELCHOL doses of 2.3 g to 3.8 g resulted in an additional 8% to 16% reduction in LDL-C above that seen with the statin alone.

Table 8 Response to WELCHOL in Combination with Atorvastatin, Simvastatin, or Lovastatin — Percent Change in Lipid Parameters
Dose/Day N TC LDL-C Apo B HDL-C * Non-HDL-C TG *
*
Median % change from baseline
p<0.05 for lipid parameters compared to placebo, for Apo B compared to baseline
Atorvastatin Trial (4-week)
Placebo 19 +4 +3 −3 +4 +4 +10
Atorvastatin 10 mg 18 −27 −38 −32 +8 −35 −24
WELCHOL 3.8 g/Atorvastatin 10 mg 18 −31 −48 −38 +11 −40 −1
Atorvastatin 80 mg 20 −39 −53 −46 +6 −50 −33
Simvastatin Trial (6-week)
Placebo 33 −2 −4 −4 −3 −2 +6
Simvastatin 10 mg 35 −19 −26 −20 +3 −24 −17
WELCHOL 3.8 g/Simvastatin 10 mg 34 −28 −42 −33 +10 −37 −12
Simvastatin 20 mg 39 −23 −34 −26 +7 −30 −12
WELCHOL 2.3 g/Simvastatin 20 mg 37 −29 −42 −32 +4 −37 −12
Lovastatin Trial (4-week)
Placebo 26 +1 0 0 +1 +1 +1
Lovastatin 10 mg 26 −14 −22 −16 +5 −19 0
WELCHOL 2.3 g/Lovastatin 10 mg Together 27 −21 −34 −24 +4 −27 −1
WELCHOL 2.3 g/Lovastatin 10 mg Apart 23 −21 −32 −24 +2 −28 −2

In all 3 studies, the LDL-C reduction achieved with the combination of WELCHOL and any given dose of statin therapy was statistically superior to that achieved with WELCHOL or that dose of the statin alone. The LDL-C reduction with atorvastatin 80 mg was not statistically significantly different from the combination of WELCHOL 3.8 g and atorvastatin 10 mg.

Pediatric Therapy

The safety and efficacy of WELCHOL in pediatric patients were evaluated in an 8-week, multicenter, randomized, double-blind, placebo-controlled, parallel-group study followed by an open-label phase, in 194 boys and postmenarchal girls 10-17 years of age (mean age 14.1 years) with HeFH, taking a stable dose of an FDA-approved statin (with LDL-C >130 mg/dL) or naïve to lipid-lowering therapy (with LDL-C >160 mg/dL). This study had 3 periods: a single-blind, placebo stabilization period; an 8-week, randomized, double-blind, parallel-group, placebo-controlled treatment period; and an 18-week, open-label treatment period. Forty-seven (24%) patients were taking statins and 147 (76%) patients were statin-naïve at screening. The mean baseline LDL-C at Day 1 was approximately 199 mg/dL.

During the double-blind treatment period, patients were assigned randomly to treatment: WELCHOL 3.8 g/day (n=64), WELCHOL 1.9 g/day (n=65), or placebo (n=65). In total, 186 patients completed the double-blind treatment period. After 8 weeks of treatment, WELCHOL 3.8 g/day significantly decreased plasma levels of LDL-C, non-HDL-C, TC, and Apo B and significantly increased HDL-C. A moderate, non-statistically significant increase in TG was observed versus placebo (Table 9).

Table 9 Response to WELCHOL 3.8 g Compared to Placebo in Pediatric Patients 10-17 Years of Age − Mean Percent Change in Lipid Parameters from Baseline to Week 8
Treatment Difference TC LDL-C Apo B HDL-C Non-HDL-C TG *
(N=128) (N=128) (N=124) (N=128) (N=128) (N=128)
Values represent LS mean. Only patients with values at both study baseline and endpoint are included in this table. Study baseline was defined as the last value measured before or on Day 1 prior to the first dose of randomized study medication.
Results were based on the ITT population with LOCF.
*
For triglycerides, median % change from baseline
p≤0.05 for lipid parameters compared to placebo
WELCHOL 3.8 g vs Placebo -7 -13 -8 +6 −11 +5

During the open-label treatment period patients were treated with WELCHOL 3.8 g/day. In total, 173 (89%) patients completed 26 weeks of treatment. Results at Week 26 were consistent with those at Week 8.

All MedLibrary.org resources are included in as near-original form as possible, meaning that the information from the original provider has been rendered here with only typographical or stylistic modifications and not with any substantive alterations of content, meaning or intent.

This site is provided for educational and informational purposes only, in accordance with our Terms of Use, and is not intended as a substitute for the advice of a medical doctor, nurse, nurse practitioner or other qualified health professional.

Privacy Policy | Copyright © 2022. All Rights Reserved.