A pharmacokinetic and tolerance study of Natroba (spinosad) Topical Suspension, 0.9% in pediatric subjects 6 months to 4 years of age with an active head lice infestation.

A Postmarketing Requirement Protocol, multicenter, open-label study in pediatric subjects 6 months to 4 years of age with an active head lice infestation designed to determine the topical absorption and safety of Natroba (spinosad) Topical Suspension, 0.9% for a single, 10 minute treatment for spinosad (Spinosyn A and Spinosyn D) and benzyl alcohol.

Inclusion Criteria:

1. Male or female, 6 months to 4 years of age.
2. Subjects must have had an active lice infestation including live lice.
3. Individuals in otherwise good general health, free of any systemic or dermatologic disorders which, in the opinion of the Principal Investigator or designee, would interfere with the study results or increase the risk of adverse events.
4. A parent (or guardian) must have signed an Informed Consent Form to allow any child to participate in the study.
5. Subjects must have been available to stay in the clinic for blood draws. Parents or guardians must have been available to stay in the clinic, with the subject, for the entire duration of the study.
6. Subjects must have had veins capable of insertion of a Heplock catheter or withstanding multiple blood draws as determined by the Principal Investigator or qualified phlebotomist.
7. Normal values (at screening) for serum chemistry and hematology for subjects, unless the principal Investigator or qualified medical designee determined that the abnormal value was not clinically significant.

Exclusion Criteria:

1. History of irritation or sensitivity to pediculicide or hair care products or ingredients.
2. History of known allergy or sensitivity to topical anesthetics including lidocaine and prilocaine.
3. History of allergy or sensitivity to Heparin.
4. Systemic diseases that could have interfered with the results of this study as determined by the Principal Investigator or designee.
5. Any condition or illness that, in the opinion of the Investigator or designee, may have compromised the objective of the protocol or the safety of the subject.
6. The use of antibiotics or other systemic medications within 2 weeks of the screening visit, which in the opinion of the Investigator or designee could have interfered with the outcome of the study.
7. Participation in a previous drug study within the past 30 days.
8. Individuals with any visible skin/scalp condition (other than from an active lice infestation) at the treatment site which would have interfered with the evaluations according to the opinion of the Investigator or designee.
9. Parents or guardians who, in the opinion of the Investigator, did not understand their child's requirements for study participation and/or may be likely to exhibit poor compliance.

Throughout the study.

All Adverse Events (AEs)occurring during the study were recorded at 0 (pretreatment), 0.5, 1, 3, 6, and 12 hours post-treatment by age group and all subjects. Verbatim descriptions of AEs were assigned to system organ classes and preferred terms using the Medical Dictionary for Regulatory Activities (MedDRA) (v14.0).

It is suspected for Subject 02-202, at 0.5 hours, the sample to determine the spinosyn A and spinosyn D concentrations were possibly contaminated with Natroba.