Efficacy and safety of spinosad and permethrin creme rinses for pediculosis capitis (head lice).
OBJECTIVE
Studies compared spinosad creme rinse and permethrin lice treatment under "actual-use" conditions for pediculosis capitis (head lice).


METHODS
Two phase-3, multicenter, randomized, evaluator/investigator-blinded studies compared 0.9% spinosad without nit-combing to 1% permethrin with combing (according to product instructions) in 1038 males and females aged > or =6 months. Spinosad-with-combing groups were included for descriptive, noninferential purposes only. Within 391 households, youngest members having > or =3 live lice were designated primary participants. All household members with lice received the same treatment. Participants administered product 1 to 2 times during the 21-day home-use period on the basis of complete lice eradication after a single use or the presence of lice requiring a second treatment. Scalp evaluations were performed at baseline, day 7, and day 14 (and day 21 for participants treated twice). The primary end point was the proportion of lice-free primary participants 14 days after last treatment.


RESULTS
A total of 84.6% (study 1) and 86.7% (study 2) of spinosad-treated participants were lice free versus 44.9% and 42.9% permethrin-treated participants (P < .001). Most spinosad-treated participants required 1 application, whereas most permethrin-treated participants required 2 applications. Few adverse events were reported, but those occurring were mild to moderate, including eye irritation (permethrin), ocular hyperemia, and application-site erythema/irritation (both medications). No laboratory measure changed significantly.


CONCLUSIONS
Spinosad, which did not require nit combing, was significantly more effective than permethrin in 2 studies reflecting actual-use conditions, and most spinosad-treated participants required only 1 application. Spinosad is a more convenient and effective treatment for pediculosis capitis.
Stough
Dow
D
Burke Pharmaceutical Research, Hot Springs, AR 71913, USA. dbs4@cablelynx.com
Shellabarger
Susan
S
Quiring
John
J
Gabrielsen
Alvin A
AA
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D004338:Drug Combinations; D005260:Female; D006801:Humans; D007223:Infant; D007306:Insecticides / Q000009:adverse effects / Q000627:therapeutic use*; D010373:Lice Infestations / Q000188:drug therapy*; D018942:Macrolides / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D026023:Permethrin / Q000009:adverse effects / Q000627:therapeutic use*; D012536:Scalp Dermatoses / Q000188:drug therapy*; D016037:Single-Blind Method; D055815:Young Adult
D004338:Drug Combinations; D007306:Insecticides; D018942:Macrolides; D026023:Permethrin; C415329:spinosad