Investigation Into the Scar Reduction Potential of Prevascar (Interleukin-10)

A Single-centre, Placebo- and Standard-care-controlled, Double-blind, Randomised Trial to Investigate the Efficacy of Eight Doses of RN1003 in the Reduction of Scarring From the Approximated Wound Margins of Incisional Wounds

The purpose of this study was to investigate the scar-reducing properties of eight doses of intradermal Prevascar (IL-10).

Subjects were randomised to one of two dose groups, each with four concentrations of intradermal Prevascar. Subjects had four 1cm incisional wounds made on the inner aspect of each upper arm (eight in total), giving four sets of anatomically paired wound sites per subject. Each subject acted as their own control with one site from each wound pair randomly treated with intradermal Prevascar and the other treated with Placebo (vehicle) or Standard Care.

Intradermal Prevascar was administered at 100μl per linear cm of wound site prior to wounding on Day 0 and 100μl per linear cm to each wound margin 24 hours later on Day 1. Group 1 subjects received doses of 5, 50, 250 and 1000ng/100μl and group 2 subjects received 25, 125, 500 and 2000ng/100μl.

Subjects in each group were also randomised into two control subgroups to receive either 100μl/linear cm intradermal placebo (Subgroup 1) or Standard Care alone (Subgroup 2) at control wound sites.

Subjects returned for follow-up at Day 14, Month 1, Month 3, Month 6, Month 9 and Month 12.

Inclusion Criteria:

• Male and female subjects, aged 18-85 years, who have given written informed consent
• Subjects with a BMI (Quetelet's index) within the permitted weight/height2 range of 15-55kg/m2
• Subjects with, in the opinion of the Investigator, clinically acceptable results for screening laboratory tests performed within 28 days prior to the first trial administration
• Female subjects with child-bearing potential who are using a method(s) of contraception deemed acceptable by the Investigator and agree to continue doing so for the first month of the trial

Exclusion Criteria:

• Subjects who, on direct questioning and by physical examination, reveal a history or evidence of hypertrophic or keloid scarring
• Subjects with tattoos or previous scars within 3cm of the area to be incised during the trial
• Subjects of Afro-Caribbean descent, because of their increased susceptibility to hypertrophic or keloid scarring
• Subjects who have had previous surgery in the area to be incised, conducted within 1 year of the first dosing day
• Subjects with a history of a bleeding disorder or who are receiving anticoagulant therapy
• Subjects who, on direct questioning and physical examination, show evidence of any past or present clinically significant disease that may affect the endpoints of the trial, e.g. coagulation disorders, diabetes, immuno- mediated conditions and clinically significant skin diseases or allergies
• Subjects with a clinically significant skin disorder that is chronic or currently active, and which the Investigator considers will adversely affect the healing of the acute wounds or involves the areas to be examined in this trial
• Subjects with any clinically significant medical condition or history that would impair wound healing, including significant rheumatoid arthritis, chronic renal impairment (significant for age), significant hepatic impairment (liver function tests >3 times upper limit of normal), congestive heart failure, active malignancy or history of malignancy within last 5 years, immunosuppression or chemotherapy within last 12 months, history of radiotherapy or diabetes mellitus
• Subjects with a history of hypersensitivity to any of the drugs or dressings used in the trial
• Subjects who are taking, or who have taken, any investigational product or participated in a clinical trial within 3 months prior to the first trial
• dose administration
• Subjects who are taking regular, continuous, oral corticosteroid therapy
• Subjects undergoing investigations or changes in management for an existing medical condition
• Subjects with a history of drug abuse, or who test positive for drugs of abuse (cocaine, amphetamines, methamphetamines, opiates or benzodiazepines) during the screening period, which is not explained by the intake of legitimate prescribed or over-the-counter medication for a documented medical condition
• Subjects who, in the opinion of the Investigator, are unlikely to complete the trial for whatever reason
• Subjects receiving immunosuppressive treatment
• Females who are pregnant or lactating
• Subjects who have any clinically significant neurological impairment or disease
• Subjects with an active infection (subjects were able to participate in the trial once the infection had passed and they had been re-screened)