13 NONCLINICAL TOXICOLOGY
Carcinogenicity studies were conducted in which modafinil (a mixture of R- and S-modafinil) was administered in the diet to mice for 78 weeks and to rats for 104 weeks at doses of 6, 30, and 60 mg/kg/day. The highest doses studied were associated with plasma modafinil exposures (AUC) less than that in humans at the recommended human dose (RHD) of modafinil (200 mg/day). There was no evidence of tumorigenesis associated with modafinil administration in these studies. However, the mouse study was inadequate because the high dose was not a maximum tolerated dose (MTD). In a mouse carcinogenicity study in which armodafinil (the R-enantiomer of modafinil) was administered at oral doses of up to 300 mg/kg/day in males and 100 mg/kg/day in females for approximately 2 years, no tumorigenic effects were observed. The highest doses studied, which were considered MTDs, were associated with plasma armodafinil exposures less than (females) or 2 times (males) that in humans at the RHD of modafinil.
Modafinil was negative in a series of in vitro (i.e., bacterial reverse mutation, mouse lymphoma tk, chromosomal aberration in human lymphocytes, cell transformation in BALB/3T3 mouse embryo cells) or in vivo (mouse bone marrow micronucleus) assays.
Impairment of Fertility
The effectiveness of modafinil in improving wakefulness in adult patients with excessive sleepiness associated with narcolepsy was established in two US 9-week, multi-center, placebo-controlled, parallel-group, double-blind studies of outpatients who met the criteria for narcolepsy. A total of 558 patients were randomized to receive modafinil 200 or 400 mg/day, or placebo. The criteria for narcolepsy include either: 1) recurrent daytime naps or lapses into sleep that occur almost daily for at least three months, plus sudden bilateral loss of postural muscle tone in association with intense emotion (cataplexy); or 2) a complaint of excessive sleepiness or sudden muscle weakness with associated features: sleep paralysis, hypnagogic hallucinations, automatic behaviors, disrupted major sleep episode; and polysomnography demonstrating one of the following: sleep latency less than 10 minutes or rapid eye movement (REM) sleep latency less than 20 minutes. For entry into these studies, all patients were required to have objectively documented excessive daytime sleepiness, via a Multiple Sleep Latency Test (MSLT) with two or more sleep onset REM periods and the absence of any other clinically significant active medical or psychiatric disorder. The MSLT, an objective polysomnographic assessment of the patient’s ability to fall asleep in an unstimulating environment, measured latency (in minutes) to sleep onset averaged over 4 test sessions at 2-hour intervals. For each test session, the subject was told to lie quietly and attempt to sleep. Each test session was terminated after 20 minutes if no sleep occurred or 15 minutes after sleep onset.
In both studies, the primary measures of effectiveness were: 1) sleep latency, as assessed by the Maintenance of Wakefulness Test (MWT); and 2) the change in the patient’s overall disease status, as measured by the Clinical Global Impression of Change (CGI-C). For a successful trial, both measures had to show statistically significant improvement.
The MWT measures latency (in minutes) to sleep onset averaged over 4 test sessions at 2 hour intervals following nocturnal polysomnography. For each test session, the subject was asked to attempt to remain awake without using extraordinary measures. Each test session was terminated after 20 minutes if no sleep occurred or 10 minutes after sleep onset. The CGI-C is a 7-point scale, centered at No Change , and ranging from Very Much Worse to Very Much Improved. Patients were rated by evaluators who had no access to any data about the patients other than a measure of their baseline severity. Evaluators were not given any specific guidance about the criteria they were to apply when rating patients.
Both studies demonstrated improvement in objective and subjective measures of excessive daytime sleepiness for both the 200 mg and 400 mg doses compared to placebo. Patients treated with modafinil showed a statistically significantly enhanced ability to remain awake on the MWT at each dose compared to placebo at final visit (Table 2). A statistically significantly greater number of patients treated with modafinil at each dose showed improvement in overall clinical condition as rated by the CGI-C scale at final visit (Table 3).
Nighttime sleep measured with polysomnography was not affected by the use of modafinil.
The effectiveness of modafinil in improving wakefulness in patients with excessive sleepiness associated with OSA was established in two multi-center, placebo-controlled clinical studies of patients who met the criteria for OSA. The criteria include either: 1) excessive sleepiness or insomnia, plus frequent episodes of impaired breathing during sleep, and associated features such as loud snoring, morning headaches and dry mouth upon awakening; or 2) excessive sleepiness or insomnia and polysomnography demonstrating one of the following: more than five obstructive apneas, each greater than 10 seconds in duration, per hour of sleep and one or more of the following: frequent arousals from sleep associated with the apneas, bradytachycardia, and arterial oxygen desaturation in association with the apneas. In addition, for entry into these studies, all patients were required to have excessive sleepiness as demonstrated by a score ≥10 on the Epworth Sleepiness Scale (ESS), despite treatment with continuous positive airway pressure (CPAP). Evidence that CPAP was effective in reducing episodes of apnea/hypopnea was required along with documentation of CPAP use.
In the first study, a 12-week trial, a total of 327 patients with OSA were randomized to receive modafinil 200 mg/day, modafinil 400 mg/day, or matching placebo. The majority of patients (80%) were fully compliant with CPAP, defined as CPAP use greater than 4 hours/night on > 70% of nights. The remainder were partially CPAP compliant, defined as CPAP use < 4 hours/night on >30% of nights. CPAP use continued throughout the study. The primary measures of effectiveness were 1) sleep latency, as assessed by the Maintenance of Wakefulness Test (MWT) and 2) the change in the patient’s overall disease status, as measured by the Clinical Global Impression of Change (CGI-C) at the final visit [see Clinical Studies ( 14.1) for a description of these measures].
Patients treated with modafinil showed a statistically significant improvement in the ability to remain awake compared to placebo-treated patients as measured by the MWT at final visit (Table 2). A statistically significant greater number of patients treated with modafinil showed improvement in overall clinical condition as rated by the CGI-C scale at final visit (Table 3). The 200 mg and 400 mg doses of modafinil produced statistically significant effects of similar magnitude on the MWT, and also on the CGI-C.
In the second study, a 4-week trial, 157 patients with OSA were randomized to receive modafinil 400 mg/day or placebo. Documentation of regular CPAP use (at least 4 hours/night on 70% of nights) was required for all patients. The primary measure of effectiveness was the change from baseline on the ESS at final visit. The baseline ESS scores for the modafinil and placebo groups were 14.2 and 14.4, respectively. At week 4, the ESS was reduced by 4.6 in the modafinil group and by 2.0 in the placebo group, a difference that was statistically significant.
Nighttime sleep measured with polysomnography was not affected by the use of modafinil.
The effectiveness of modafinil in improving wakefulness in patients with excessive sleepiness associated with SWD was demonstrated in a 12-week placebo-controlled clinical trial. A total of 209 patients with chronic SWD were randomized to receive modafinil 200 mg/day or placebo. All patients met the criteria for chronic SWD. The criteria include: 1) either, a) a primary complaint of excessive sleepiness or insomnia which is temporally associated with a work period (usually night work) that occurs during the habitual sleep phase, or b) polysomnography and the MSLT demonstrate loss of a normal sleep-wake pattern (i.e., disturbed chronobiological rhythmicity); and 2) no other medical or mental disorder accounts for the symptoms, and 3) the symptoms do not meet criteria for any other sleep disorder producing insomnia or excessive sleepiness (e.g., time zone change [jet lag] syndrome).
It should be noted that not all patients with a complaint of sleepiness who are also engaged in shift work meet the criteria for the diagnosis of SWD. In the clinical trial, only patients who were symptomatic for at least 3 months were enrolled.
Enrolled patients were also required to work a minimum of 5 night shifts per month, have excessive sleepiness at the time of their night shifts (MSLT score < 6 minutes), and have daytime insomnia documented by a daytime polysomnogram.
The primary measures of effectiveness were 1) sleep latency, as assessed by the MSLT performed during a simulated night shift at the final visit and 2) the change in the patient’s overall disease status, as measured by the CGI-C at the final visit [see ClinicalStudies( 14.1) for a description of these measures.].
Patients treated with modafinil showed a statistically significant prolongation in the time to sleep onset compared to placebo-treated patients, as measured by the nighttime MSLT at final visit (Table 2). A statistically significant greater number of patients treated with modafinil showed improvement in overall clinical condition as rated by the CGI-C scale at final visit (Table 3).
Daytime sleep measured with polysomnography was not affected by the use of modafinil.
|Disorder||Measure||Modafinil tablets 200 mg*||Modafinil tablets 400 mg*||Placebo|
|Baseline||Change from Baseline||Baseline||Change from Baseline||Baseline||Change from Baseline|
* Significantly different than placebo for all trials (p<0.01 for all trials but SWD, which was p<0.05)
|Disorder||Modafinil tablets 200 mg*||Modafinil tablets 400 mg*||Placebo|
*Significantly different than placebo for all trials (p<0.01)
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.