Background: Hidradenitis suppurativa (HS) is a chronic, inflammatory, burdensome skin disease where medical first-line treatment is still limited to long-term, topical and/or systemic antibiotics. The RELIEVE study aimed at evaluating the efficacy of LAight® therapy – a combination of intense pulsed light and radiofrequency – as an adjunct treatment to first-line therapies in Hurley stage I and II HS. Methods: The RELIEVE study was performed as a two-period multicenter randomized controlled trial with blinded assessment. For period A from week 0 to week 16, the 88 participating subjects were randomized into either an intervention group (IG) or a control group (CG). The IG received topical clindamycin 1% solution combined with 8 additional bi-weekly treatments with LAight® therapy. The CG was treated with topical clindamycin 1% solution only. After 16 weeks, patients entered open-label period B and both groups were treated exclusively with LAight® therapy for an additional 16 weeks (8 sessions). The primary efficacy endpoint was the change in International Hidradenitis Suppurativa Score System (∆IHS4) at week 16 to baseline. Secondary endpoints were DLQI, HiSCR, Pain-NRS, and HADS. Results: In total, from the 88 patients enrolled in RELIEVE, 81 patients were included in the endpoint analysis after period A. After 16 weeks of treatment, the ∆IHS4 of the group treated with the combination of LAight® therapy and topical clindamycin 1% solution was −7.2 ± 6.7 (−60.0%), which was significantly higher in magnitude than the ∆IHS4 in the group treated with clindamycin 1% solution alone (−1.8 ± 5.6, −17.8%, p < 0.001). Secondary endpoints, including other clinical scores as well as patient-reported outcomes, confirmed that the efficacy of the combined treatment was superior to monotherapy. Conclusion: The results of the primary endpoint analysis of period A of the RELIEVE study show that the combined therapy with LAight® and topical clindamycin 1% solution, resulted in a significantly higher decrease in disease severity and an improvement of quality of life in comparison to topical clindamycin 1% solution monotherapy. Treatment was well tolerated, and side effects were all mild and transitory. These data speak for the implementation of the combined treatment as a first-line therapy in Hurley stage I and II HS. LAight® therapy as long-term monotherapy (results from period B), will be analyzed in a consecutive paper.