Clinical study of short-term and delayed efficacy of isotretinoin in treatment of patients with acne vulgaris and acne conglobata

Objective — to determine the long-term effectiveness of isotretinoin Lidose in comparison with classic isotretinoin. Materials and methods. The study included 194 patients (124 women and 70 men) aged 18—40 years with moderate and severe acne. Depending on the treatment method, the patients were divided into two groups. Group A (comparison) included 95 patients with acne vulgaris or conglobata who used isotretinoin; group B (experimental) included 99 patients who used Isotretinoin Lidose. The examination was performed before treatment, 3 and 6 months after its initiation. After 6 months, patients of both groups were divided into 4 subgroups each depending on the cumulative dose of received isotretinoin: A1 — received less than 120 mg/kg of regular isotretinoin; B1 — less than 120 mg/kg of isotretinoin Lidose; A2 — 120 mg/kg of regular isotretinoin; B2 — 120 mg/kg of isotretinoin Lidose; A3 — 150 mg/kg of regular isotretinoin; B3 — 150 mg/kg of isotretinoin Lidose; A4 — more than 150 mg/kg of regular isotretinoin due to additional administration of 10 mg/day after reaching the cumulative dose by the 12th month of treatment; B4 — more than 150 mg/kg of isotretinoin Lidose due to additional administration of 8 mg/day after reaching the cumulative dose by the 12th month of treatment. Patients of 8 subgroups were examined 12 months after treatment initiation. A score assessment of acne severity was performed using the IGA scale, and a questionnaire was administered to patients and doctors to assess the effectiveness of treatment 6 and 12 months after the start of therapy. The assessment of quality of life was carried out using the authorized Ukrainian translation of the DLQI. Results and discussion. Patients had less acne elements count and a lower IGA score in the group receiving isotretinoin Lidose at 3 and 6 months after the initiation of treatment compared to classic isotretinoin. In subgroups of patients receiving isotretinoin Lidose the number of post-acne scars was 14—30 % lower in 12 months after the initiation of therapy than in subgroups receiving classic isotretinoin. Relapses were more common in subgroups that did not receive the full cumulative dose of isotretinoin (less than 120 mg/kg). Analysis of the assessment of the effectiveness of therapy by patients and doctors in 12 months after its initiation showed similar results: a higher assessment score with isotretinoin Lidose compared to the corresponding cumulative doses with classic isotretinoin. Assessment of life quality in subgroups in 12 months after treatment initiation showed statistically better results in subgroups receiving isotretinoin Lidose compared to subgroups using classic isotretinoin. Conclusions. The use of isotretinoin Lidose provides a significantly better reduction in the number of acne elements and the IGA score compared to classic isotretinoin. The use of isotretinoin Lidose in the treatment of moderate and severe forms of acne reduces the post-acne scars and the disease relapse. The most effective cumulative dose of isotretinoin to prevent recurrence of acne vulgaris and acne conglobata is 150 mg/kg with a subsequent low maintenance dose of 8—10 mg/day.