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Phase 3 Trial to Assess the Safety and Efficacy of Natroba for the Treatment of Scabies

A Phase 3, Randomized, Double Blind, Placebo-Controlled Study to Assess the Safety and Efficacy of Natroba™ (Spinosad) for the Treatment of Scabies

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02485704
Enrollment
280
Registered
2015-06-30
Start date
2017-05-10
Completion date
2018-08-03
Last updated
2021-05-21

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Scabies

Brief summary

To assess the safety and efficacy of Natroba (spinosad) topical suspension versus placebo for the complete cure of scabies after a single treatment.

Detailed description

This is a double blind, two-arm, 28-day, placebo-controlled study with approximately 120 infested index subjects randomized 1:1 to Natroba™ or Placebo. All members of a household (no more than 6 individuals) with a suspected index subject must be screened at the first visit. In this study, index subjects are defined as the youngest infested household member (≥4 years). If the members have an active scabies infestation and meet all other criteria, they must agree to participate in the study. Household members who do not present with scabies at the screening visit must also agree to apply the same blinded investigational product (IP) as household members who present with scabies. All infested household members must agree to participate in the study or none will be enrolled. Screening procedures include informed consent, medication and medical history, urine pregnancy test for females of childbearing potential, scabies assessment (visual evidence of burrows, inflammatory/non-inflammatory lesions and pruritus), microscopic examination of skin scraping, or dermatoscopy, to demonstrate the presence of mites, eggs, and/or scybala (dermatoscopy must confirm burrows), vital signs, general skin and eye assessment, randomization, and IP dispensing and instruction. After screening on Day 1, all randomized subjects will be dispensed IP (Natroba™ or Placebo) to apply at home later the same day as a single treatment over the entire body from the neck down to the toes (including the soles of the feet) and to the scalp (if balding) or hairline, temples and forehead on the same day. Subjects less than 12 years of age should be assisted with administration by a parent, guardian or caregiver. Subjects will rub the treatment into the skin followed by a 10-minute wait period before getting dressed. Showering or bathing must not occur earlier than 6 hours after treatment and no later than at least 1 hour prior to Day 2 visit. On Day 2 (Visit 2), all household members will return for general skin and eye assessments of possible irritation, and to confirm that all IP was left on for a minimum of 6 hours before bathing or showering. If a subject reports an adverse event assessed as related by the PI on Day 2 (Visit 2) then a follow-up visit with the investigator must be scheduled within 7 days of visit. All household members will receive a well-being phone call on Day 14 to continue to emphasize instructions to prevent re-infestation, determine if any concomitant medications have been used, and check for adverse events. If a subject reports an adverse event assessed as related by the PI on the Day 14 well-being phone call, then a follow-up visit with the investigator must be scheduled within 7 days of phone call. On Day 28 (Visit 3), all household members will return to the clinic for safety and efficacy assessments. The primary endpoint of complete cure will be assessed in the index subject and any infested household members. If the infested subject is completely cured at Day 28, he or she will have completed the study and termination procedures will be conducted. If the subject is not completely cured at Day 28 (with Natroba™ or Placebo), the subject will receive 5% Permethrin and will be directed to their primary care physician for follow-up. Safety assessments will be made for all household members and will include monitoring of adverse events (AEs) throughout the study, vital signs recording (Days 1 and 28), clinical laboratory analyses (Days 1 and 28), and general skin and eye irritation assessments (Days 1, 2, and 28). The Day 28 procedures will also be completed for early termination (ET) except subjects will not receive rescue Permethrin but will be directed to follow-up with their primary care physician.

Interventions

Topically apply 0.9% suspension up to 120 mL (enough to cover the body from the neck down to the soles of the feet). One application for six hours.

OTHERPlacebo

Placebo is the same as the drug minus the active ingredient spinosad (vehicle). Topically apply up to 120 mL (enough to cover the body from the neck down to the soles of the feet). One application for six hours.

Sponsors

Concentrics Research
CollaboratorOTHER
ParaPRO LLC
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
4 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* All household members who have provided written informed consent and an authorization for disclosure of protected health information must meet all the following criteria: 1. Male or female, age 4 years and upward. 2. At least one household member must have active scabies infestation confirmed by clinical signs and symptoms (evidence of burrows or presence of scabies inflammatory/non-inflammatory lesions and pruritus) as well as by microscopic examination of skin scraping, or dermatoscopy, to demonstrate the presence of mites, eggs, and/or scybala. If dermatoscopy is used it should also confirm there are burrows on the skin. 3. Generally in good health based on medical history and clinical assessments. 4. Normal-appearing skin in noninfested areas. 5. No history of chronic or recurrent dermatologic disease. 6. Willingness to comply with the study procedures including application of study treatment at home as instructed. 7. Willing and able to practice an acceptable measure of contraception during the study, if female of childbearing potential. Examples of acceptable contraceptive methods include abstinence, intrauterine device (IUD), double barrier method, oral or implantable or injectable contraceptives. Must have been using systemic (oral, injectable, or implantable) contraceptives for at least 3 months. If abstinent and planning to become sexually active must agree to use a double barrier method. 8. Subject agrees to inform their sexual partners to seek an examination for scabies and treatment if, and when, symptoms present. 9. Household members must be 6 or fewer and all members must be willing to attend clinic visits and be randomized to treatment (blinded, but same for all).

Exclusion criteria

* All household members must be excluded if any of the following conditions are met: 1. Household has greater than 6 residents. 2. Has a household member(s) who is not willing or not eligible to enroll. 3. Presence of scabies on the scalp. 4. Presence of crusted scabies (Norwegian scabies). 5. Allergies or intolerance to ingredients in the IPs. 6. Current pregnancy (as assessed by urine pregnancy test) or currently nursing. 7. The household has sexually active subjects who do not agree to restrict prolonged skin to skin contact with non-household members during the trial period. 8. Known renal or hepatic impairment. 9. Treatment with scabicide within the prior 4 weeks. 10. Immunodeficiency (including HIV infection) as reported by the subject in Medical History. 11. Signs or symptoms of systemic infection. 12. Administration of any systemic therapy for infectious disease within the prior 2 weeks. 13. Receipt of any other investigational product (IP) within the prior 4 weeks. 14. Any other conditions that, at the investigator's discretion, may interfere with the study conduct, or which might confound the interpretation of the study results, or which may put the subject at undue risk. 15. Does not have a known household affiliation with their household members (stays in one household inconsistently, i.e., sleeps at one place several nights and then other places on other nights). 16. Household member is unwilling to treat scabies.

Design outcomes

Primary

MeasureTime frameDescription
Number of Index Subjects Completely Cured of Scabies After a Single Treatment28 days after treatmentThe primary efficacy assessment is the proportion of index subjects completely cured of scabies by Day 28. Complete cure is defined as a demonstration of both clinical cure (all signs and symptoms have completely resolved, including burrows, inflammatory/non-inflammatory lesions and pruritus) and microscopic or dermatoscopic cure demonstrating the absence of mites, eggs, and/or scybala, and a negative dermatoscopy for burrows.

Countries

United States

Participant flow

Recruitment details

18 subjects were excluded from the ITT (intent-to-treat), I-ITT (index intent-to-treat), and I-PP (index per protocol) populations due to noncompliance with the randomization procedures. As such, only 262 subjects (145 in the Natroba group and 117 in the placebo group) were included in the ITT population.

Pre-assignment details

Inclusion Criteria #2 - At least one household member must have active scabies infestation confirmed.

Participants by arm

ArmCount
Natroba (Spinosad)
Spinosad topical suspension, 0.9% up to 120 mL (enough product is used to cover the body from the neck down to the soles of the feet), one treatment left on for 6 hours Spinosad topical suspension, 0.9%: Topically apply 0.9% suspension up to 120 mL (enough to cover the body from the neck down to the soles of the feet). One application for six hours.
145
Placebo
Placebo is a topical suspension that is the same formulation as Natroba without the active ingredient, spinosad (vehicle). Up to 120 mL (enough product is used to cover the body from the neck down to the soles of the feet), one treatment left on for 6 hours. Placebo: Placebo is the same as the drug minus the active ingredient, spinosad (vehicle). Topically apply up to 120 mL (enough to cover the body from the neck down to the soles of the feet). One application for six hours.
117
Total262

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyDid Not Meet Inclusion Criteria #210
Overall StudyLost to Follow-up45
Overall StudyWithdrawal by Subject03

Baseline characteristics

CharacteristicNatroba (Spinosad)TotalPlacebo
Active Scabies Infestation92 Participants161 Participants69 Participants
Age, Categorical
<=18 years
47 Participants85 Participants38 Participants
Age, Categorical
>=65 years
14 Participants17 Participants3 Participants
Age, Categorical
Between 18 and 65 years
84 Participants160 Participants76 Participants
Age, Continuous33.7 years32.8 years31.7 years
Evidence of Burrows90 Participants158 Participants68 Participants
Evidence of Lesions103 Participants182 Participants79 Participants
Evidence of Pruritus113 Participants202 Participants89 Participants
Microscopy/Dermatoscopy Result
Negative
53 Participants101 Participants48 Participants
Microscopy/Dermatoscopy Result
Positive
92 Participants161 Participants69 Participants
Prior Scabies Infestation68 Participants136 Participants68 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
7 Participants14 Participants7 Participants
Race (NIH/OMB)
Black or African American
24 Participants38 Participants14 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants2 Participants2 Participants
Race (NIH/OMB)
Unknown or Not Reported
2 Participants4 Participants2 Participants
Race (NIH/OMB)
White
112 Participants204 Participants92 Participants
Region of Enrollment
United States
145 participants262 participants117 participants
Score of Pre-Existing Lesions
≤ 10 Lesions (Mild)
48 Participants82 Participants34 Participants
Score of Pre-Existing Lesions
11-49 Lesions (Moderate)
55 Participants100 Participants45 Participants
Score of Pre-Existing Lesions
≥ 50 Lesions (Severe)
0 Participants0 Participants0 Participants
Score of Pre-Existing Lesions
Free of Lesions
41 Participants79 Participants38 Participants
Score of Pre-Existing Lesions
Not Done
1 Participants1 Participants0 Participants
Sex: Female, Male
Female
78 Participants145 Participants67 Participants
Sex: Female, Male
Male
67 Participants117 Participants50 Participants
Total Number of Pre-existing Lesions8.6 lesions8.2 lesions7.7 lesions

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 1450 / 135
other
Total, other adverse events
3 / 1451 / 135
serious
Total, serious adverse events
0 / 1450 / 135

Outcome results

Primary

Number of Index Subjects Completely Cured of Scabies After a Single Treatment

The primary efficacy assessment is the proportion of index subjects completely cured of scabies by Day 28. Complete cure is defined as a demonstration of both clinical cure (all signs and symptoms have completely resolved, including burrows, inflammatory/non-inflammatory lesions and pruritus) and microscopic or dermatoscopic cure demonstrating the absence of mites, eggs, and/or scybala, and a negative dermatoscopy for burrows.

Time frame: 28 days after treatment

Population: Participants analyzed are based on the number of subjects who had no missing observations in each study group.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Natroba (Spinosad)Number of Index Subjects Completely Cured of Scabies After a Single Treatment52 Participants
PlaceboNumber of Index Subjects Completely Cured of Scabies After a Single Treatment20 Participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026