Active Comparator: RID shampoo The RID shampoo is to be applied on dry the hair for 10 minutes and then rinsed out with water. the product is to be applied on Day 0 and repeated again on Day 7.

The % of subjects with a mild (5-9 lice and/or nymphs) and moderate (10-24 lice and/or nymphs) baseline infestation that are lice-free after two topical treatments (day 0 & day 7) with the test product; assessed at study end (visit 4; day 10).

The % of subjects with a mild (5-9 lice and/or nymphs) and moderate (10-24 lice and/or nymphs) baseline infestation that are lice-free after two topical treatments (day 0 & day 7) with the reference product; assessed at study end (visit 4; day 10).

The % of subjects that are lice-free after one topical treatment with the test product (assessment 24h post treatment), considering all baseline infestations (mild, moderate, severe).

A mild infestation corresponds to 5-9 lice and/or nymphs A moderate infestation corresponds to 10-24 lice and/or nymphs A severe infestation corresponds to 25 or more lice and/or nymphs

The % of subjects that are lice-free after one topical treatment with the reference product (assessment 24h post treatment), considering all baseline infestations (mild, moderate, severe).

A mild infestation corresponds to 5-9 lice and/or nymphs A moderate infestation corresponds to 10-24 lice and/or nymphs A severe infestation corresponds to 25 or more lice and/or nymphs

The occurrence and degree of pruritus is rated by the blinded clinical investigator at each visit, using the following scores: none (best outcome), mild, moderate, and severe (worst outcome).

None: the scalp does not itch; Mild: occasional episodes of itching, not bothersome; Moderate: frequent, several times a day, bothersome; Severe: nearly constant, frequent scratching, very bothersome.

The occurrence and degree of scalp excoriation (breaking of the skin, usually caused by scratching) is rated by the blinded clinical investigator at each visit, using the following scores: none (best outcome), mild, moderate, and severe (worst outcome).

None: no broken skin on the scalp; Mild: one or two areas on the scalp on which skin is broken; Moderate: more than two separate areas of the scalp with broken skin but not generalized across the scalp; Severe: widespread breaking of the skin involving most of the scalp.

The occurrence and degree of paraesthesia (tingling or prickling sensation) is rated by the blinded clinical investigator at each visit, using the following scores: none (best outcome), mild, moderate, and severe (worst outcome).

None: no tingling or prickling sensation; Mild: occasional tingling or prickling sensation; Moderate: frequent tingling or prickling sensation; Severe: nearly constant tingling or prickling sensation

The occurrence and degree of skin erythema (redness of the scalp) is rated by the blinded clinical investigator at each visit, using the following scores: none (best outcome), mild, moderate, and severe (worst outcome).

None: no redness of the scalp; Mild: faint, barely perceptible erythema with limited distribution; Moderate: diffuse pink areas of scalp are readily visible; Severe: large areas of the scalp are red.

The occurrence and degree of pyroderma (sores filled with clear fluid, pus or crusting) is rated by the blinded clinical investigator at each visit, using the following scores: none (best outcome), mild, moderate, and severe (worst outcome).

None: no lesions visible on the scalp; Mild: one or two lesions visible with crusting or other evidence of infection; Moderate: presence of more than two lesions with crusting or other evidence of infection, but not generalized across the scalp; Severe: lesions with crusting or other evidence of infection, involving most of the scalp.

The occurrence and degree of eye irritation (stinging, burning sensation, and/or pain) is rated by the blinded clinical investigator at each visit, using the following scores: none (best outcome), mild, moderate, and severe (worst outcome).

None: no stinging, burning or pain Mild: slight mild stinging, burning or pain Moderate: moderate stinging, burning or pain Severe: severe stinging, burning or pain

Global tolerability is defined as the general well-being and comfort of the subjects. This parameter is assessed at day 10 in subjects, treated with either test product or reference product, respectively. The subject is asked to score his general feeling at study end and must provide a justification for his/her answer. Scoring was performed as follows: very good (best case), good, moderate, or poor (worst case).

Clinical efficacy is reflected by the % of subjects that are lice-free after 2 topical applications (at day 0 & day 7 respectively) of the reference product. In this analysis, all baseline infestations (mild, moderate, severe) have been included. Assessment is performed at study end (visit 4, day 10).

A mild infestation corresponds to 5-9 lice and/or nymphs A moderate infestation corresponds to 10-24 lice and/or nymphs A severe infestation corresponds to 25 or more lice and/or nymphs

In the first analysis, all subjects treated with the reference product (n=35), have been analyzed (no correction for re-infestation). In a second analysis, a correction for re-infestation, defined as (1) no adult lice or third-stage nymphs present following the first treatment, and (2) no more than two adult lice or third-stage nymphs found on day 10, has been performed. Results are indicated in the table below.

The % of subjects with a mild (5-9 lice and/or nymphs) and moderate (10-24 lice and/or nymphs) baseline infestation that are lice-free after two topical treatments (day 0 & day 7) with the test product; assessed at study end (visit 4; day 10).

28 subjects with light to moderate infestation (5-25 lice) and treated with test product have been included in this analysis. Subjects with severe infestation (>25 lice; n=7) were excluded.

The % of subjects with a mild (5-9 lice and/or nymphs) and moderate (10-24 lice and/or nymphs) baseline infestation that are lice-free after two topical treatments (day 0 & day 7) with the reference product; assessed at study end (visit 4; day 10).

33 subjects with mild to moderate infestation, treated with reference product, have been included in this analysis. Subjects with severe infestation (>25 lice; n=2) were excluded.

The % of subjects that are lice-free after one topical treatment with the test product (assessment 24h post treatment), considering all baseline infestations (mild, moderate, severe).

A mild infestation corresponds to 5-9 lice and/or nymphs A moderate infestation corresponds to 10-24 lice and/or nymphs A severe infestation corresponds to 25 or more lice and/or nymphs

The % of subjects that are lice-free after one topical treatment with the reference product (assessment 24h post treatment), considering all baseline infestations (mild, moderate, severe).

A mild infestation corresponds to 5-9 lice and/or nymphs A moderate infestation corresponds to 10-24 lice and/or nymphs A severe infestation corresponds to 25 or more lice and/or nymphs

The occurrence and degree of pruritus is rated by the blinded clinical investigator at each visit, using the following scores: none (best outcome), mild, moderate, and severe (worst outcome).

None: the scalp does not itch; Mild: occasional episodes of itching, not bothersome; Moderate: frequent, several times a day, bothersome; Severe: nearly constant, frequent scratching, very bothersome.

Concerns a safety parameter. The safety set/population consists of all subjects who were randomised and exposed to study medication. The table below shows the total number of participants in each test group, experiencing mild to severe pruritus (combined), at the different evaluation time points.

The occurrence and degree of scalp excoriation (breaking of the skin, usually caused by scratching) is rated by the blinded clinical investigator at each visit, using the following scores: none (best outcome), mild, moderate, and severe (worst outcome).

None: no broken skin on the scalp; Mild: one or two areas on the scalp on which skin is broken; Moderate: more than two separate areas of the scalp with broken skin but not generalized across the scalp; Severe: widespread breaking of the skin involving most of the scalp.

Concerns a safety parameter. The safety set/population consists of all subjects who were randomised and exposed to study medication. The table below shows the total number of participants in each test group, experiencing mild to severe scalp excoriation (combined), at the different evaluation time points.

The occurrence and degree of paraesthesia (tingling or prickling sensation) is rated by the blinded clinical investigator at each visit, using the following scores: none (best outcome), mild, moderate, and severe (worst outcome).

None: no tingling or prickling sensation; Mild: occasional tingling or prickling sensation; Moderate: frequent tingling or prickling sensation; Severe: nearly constant tingling or prickling sensation

Concerns a safety parameter. The safety set/population consists of all subjects who were randomised and exposed to study medication. The table below shows the total number of participants in each test group, experiencing mild to severe paraesthesia (combined), at the different evaluation time points.

The occurrence and degree of skin erythema (redness of the scalp) is rated by the blinded clinical investigator at each visit, using the following scores: none (best outcome), mild, moderate, and severe (worst outcome).

None: no redness of the scalp; Mild: faint, barely perceptible erythema with limited distribution; Moderate: diffuse pink areas of scalp are readily visible; Severe: large areas of the scalp are red.

Concerns a safety parameter. The safety set/population consists of all subjects who were randomised and exposed to study medication. The table below shows the total number of participants in each test group, experiencing mild to severe skin erythema (combined), at the different evaluation time points.

The occurrence and degree of pyroderma (sores filled with clear fluid, pus or crusting) is rated by the blinded clinical investigator at each visit, using the following scores: none (best outcome), mild, moderate, and severe (worst outcome).

None: no lesions visible on the scalp; Mild: one or two lesions visible with crusting or other evidence of infection; Moderate: presence of more than two lesions with crusting or other evidence of infection, but not generalized across the scalp; Severe: lesions with crusting or other evidence of infection, involving most of the scalp.

Concerns a safety parameter. The safety set/population consists of all subjects who were randomised and exposed to study medication. The table below shows the total number of participants in each test group, experiencing mild to severe pyroderma (combined), at the different evaluation time points.

The occurrence and degree of eye irritation (stinging, burning sensation, and/or pain) is rated by the blinded clinical investigator at each visit, using the following scores: none (best outcome), mild, moderate, and severe (worst outcome).

None: no stinging, burning or pain Mild: slight mild stinging, burning or pain Moderate: moderate stinging, burning or pain Severe: severe stinging, burning or pain

Concerns a safety parameter. The safety set/population consists of all subjects who were randomised and exposed to study medication. The table below shows the total number of participants in each test group, experiencing mild to severe eye irritation (combined), at the different evaluation time points.

Global tolerability is defined as the general well-being and comfort of the subjects. This parameter is assessed at day 10 in subjects, treated with either test product or reference product, respectively. The subject is asked to score his general feeling at study end and must provide a justification for his/her answer. Scoring was performed as follows: very good (best case), good, moderate, or poor (worst case).

All subjects that have been treated at D0 & D7 with test or reference product, respectively.

Recording Adverse Events and investigating the relationship with the treatment. At each visit (D0: first treatment; D1: 24h post-treatment assessment; D7: second treatment; D10: final assessment), the clinical staff is recording adverse events (if any) and evaluates the correlation with the treatment.

All subjects that have been exposed to at least 1 treatment (either test product or reference).

Commercial, pyrethrin-based shampoo (RID shampoo)

RID shampoo: Active Comparator: RID shampoo The RID shampoo is to be applied on dry the hair for 10 minutes and then rinsed out with water. the product is to be applied on Day 0 and repeated again on Day 7.