Longitudinal monitoring of CYP3A activity in patients receiving 3 cycles of itraconazole pulse therapy for onychomycosis

CYP3A but not P-gp plays a relevant role in the in vivo intestinal and hepatic clearance of the delta-specific phosphoinositide-3 kinase inhibitor leniolisib

This study investigated the effect of itraconazole, a strong dual inhibitor of cytochrome P450 (CYP) 3A4 and P-glycoprotein (P-gp), on the single dose pharmacokinetics of leniolisib. In order to differentiate the specific contribution of CYP3A from P-gp, the potential interaction with quinidine, a strong inhibitor of P-gp but not CYP3A, was studied as well. Using a fixed-sequence, 3-way crossover design, 20 healthy male subjects received single oral doses of 10 mg leniolisib during three phases separated by a washout: (1) leniolisib alone, (2) 200 mg itraconazole once daily for 9 days plus leniolisib on day 5, and (3) 300 mg quinidine administered 1 h before and 3 h after leniolisib. Itraconazole increased the leniolisib oral drug exposure (AUC_inf ) by on average 2.1-fold, whereas the peak drug concentration (C_max ) was less impacted (1.25-fold). The terminal elimination half-life (T_1/2 ) of leniolisib was also increased by ~2-fold. Neither oral AUC_inf nor C_max or T_1/2 was found to be altered by quinidine. These findings suggest that the interaction with itraconazole occurred mainly systemically through inhibition of CYP3A, and corroborate our in vitro findings that leniolisib is neither a sensitive CYP3A substrate nor a relevant in vivo substrate for intestinal or hepatic P-gp. Assuming itraconazole levels achieved complete inhibition of CYP3A, the fractional contribution of CYP3A to the overall disposition of leniolisib is estimated to be about 50%. The concomitant use of leniolisib with strong inhibitors of CYP3A as well as strong and moderate inducers of CYP3A is best avoided.

An exploration of the optimum dosage and number of cycles of itraconazole pulse therapy for severe onychomycosis

Although standard itraconazole pulse therapy is a well-established regimen for toenail onychomycosis, the cure rate for onychomycosis remains low. To evaluate the efficacy and safety of different cycles of itraconazole pulse therapy, determine the optimal dosage and number of cycles for onychomycosis. A total of 90 outpatients of our hospital with onychomycosis were randomised into three treatment groups: (1) standard itraconazole pulse therapy (200 mg twice per day, 1 week each month for three pulses); (2) long-term pulse therapy (200 mg twice per day, 1 week each month for six pulses); (3) low-dose and long-term pulse therapy (200 mg/d, 1 week per month for six pulses) and were followed up for 15 months. Of the initial patients, the trial was completed by 81 patients. The complete cure rates were 32.43% for three cycles and 75% for six cycles (P < .001). For six cycles, despite the administration of half-dose for patients weighing no more than 55 kg, there was no statistical difference in the complete cure rate (P = .862). Long-term therapy is effective and safe for the treatment of toenail onychomycosis. For patients weighing no more than 55 kg, long-term half-dose itraconazole pulse therapy is recommended .

Self-controlled Study of Onychomycosis Treated with Long-pulsed Nd:YAG 1064-nm Laser Combined with Itraconazole

Background:

Onychomycosis is a fungal infection of the nail plate and subungual area. In this study, we examined the efficacy of laser treatment using self-controlled study programs involving a long-pulsed Nd:YAG 1064-nm laser combined with oral medication.

Methods:

Self-controlled strategies were followed in this study. The patients received treatment with oral itraconazole in conjunction with long-pulsed Nd:YAG 1064-nm laser treatment at the nails of the unilateral limb once a week for a total of four times. A total of 84 affected nails were divided into Group A (mild to moderate) and Group B (severe) according to disease severity. Affected nails with the same Scoring Clinical Index for Onychomycosis scores were selected to compare the therapeutic effects of the pure medication treatment group and the combination treatment group with a 24-week follow-up period.

Results:

In Group A, at the 8^th, 16^th, and 24^th weeks of follow-up, the efficacies in the pure medication treatment group were 81.0%, 81.0%, and 90.5%, respectively, while those in the combination treatment group were 100%, 95.2%, and 90.5%, respectively. The differences between groups were not significant (8^th week: χ² = 4.421, P > 0.05; 16^th week: χ² = 2.043, P > 0.05; 24^th week: χ² = 0.00, P > 0.05). In Group B, at the 8^th, 16^th, and 24^th weeks of follow-up, the efficacies in the pure medication treatment group were 61.9%, 66.7%, and 52.4%, respectively, while those in the combination treatment group were 95.2%, 90.5%, and 100%, respectively. The differences between groups at the 8^th and 24^th weeks of follow-up were statistically significant (8^th week: χ² = 6.929, P < 0.05; 24^th week: χ² = 13.125, P < 0.05).

Conclusions:

For patients with mild or moderate onychomycosis, we recommended a pure medication treatment or combination treatment with medication and laser. For those patients with severe onychomycosis, we recommended a combination of medication and laser therapy.