This randomized, double-blind controlled study aims to compare the effect on appearance of post- surgical scars between daily application of siSPARC microneedle patch versus siSPARC + siLR4A microneedle patches. These are patches comprising short microneedles embedded with hydrolysed RNA (siRNAs).

This is an 8-week, single centre double-blinded intra-individually controlled trial to compare the effect of daily application of siSPARC microneedle patch versus siSPARC + siLR4A microneedle patch on post-surgical scars. At least 50 subjects will be recruited for the study. After the patients have been screened for study eligibility by the study investigators or coordinators, the subjects who have understood and signed the informed consent will be enrolled in the study. Provided a subject satisfies all inclusion criteria and does not fall within exclusion criteria during the screening visit, that subject will be started on the trial during that same visit. Computer-generated randomisation will be performed to determine the randomization of patient population to the siSPARC microneedle patch or siSPARC + siLR4A microneedle patch. Subsequent follow-up visits would be on Day 30 and Day 60. A deviation of +/- 7 days will be accepted during the follow-up. Each study visit will last between 30-60 minutes.

Study investigators and coordinators will be performing the following assessments:

1. High resolution 3D imaging: Scar elevation will be measured using the Space Spider 3D scanner, with a resolution of 0.1 mm and a blue light-emitting diode (LED) light source;
2. Vancouver scar scale (VSS) score;
3. Scar Cosmesis Assessment and Rating (SCAR) scale score from the photographs;
4. Change in patient-reported levels of pain and itch using a 11-point numerical rating scale; and
5. Assessment of side effects (if any). Photographic documentation: Photographic documentation will be performed at baseline and during the specified follow-up examinations. Images will be taken with standardized camera settings and standardized positioning of the subject. These images will be assessed by investigators to assess the change in scar appearance.

The siRNA microneedle patches are not commercially available. These patches have undergone testing with guinea pigs and white rabbits and were ascertained as a 'non-sensitiser' and 'non- irritant', respectively. The patches have also underwent testing to L-929 cells which are adherent cells of mouse fibroblast cell line and found to be 'non-cytotoxic'. This study involves a trial comparing treatment outcomes; there is no investigative work conducted and hence no incidental findings are not anticipated.

Inclusion Criteria:

• Adult
• Age 21-75
• 2 weeks (+/- 7 days) after surgical operation with incision into the dermis
• Post-stitch removal when stitches were applied
• Wound closure/union achieved

Exclusion Criteria:

• Pregnant or lactating participant
• Participants with wound infection
• Participants assessed to be uncooperative or unable to self-administer the interventions
• Participants with known contact allergy to ingredients in the patch formulation (comprising hyaluronic acid, siRNA and glue) and/or isopropyl alcohol
• Participants who are unable to personally consent (for e.g., cognitively impaired)