Acne vulgaris is a disorder of the pilosebaceous unit that primarily affects adolescents. Cutibacterium acnes(formerly known as P.acnes) which is a commensal bacterium of the cutaneous microbiome playing a crucial role in acne development.Acne is the most common skin disease of adolescence, affecting over 80% of teenagers (aged 13-18 years) at some point. Classically, the pathogenesis of acne has been linked to four key processes viz increased sebum production,alteration of follicular keratinization leading to comedone formation,colonization of the follicle by Cutibacterium acnes,inflammation of pilosebaceous unit. Primary acne lesions include micro-comedones, comedones, papules,pustules,nodules & cysts.Secondary acne lesions include macular erythema, macular pigmentation,atrophic scars & hypertrophic/ keloidal scars. Benzoyl peroxide (BPO) is an effective antimicrobial (bactericidal) & anti-inflammatory and has rapid action, destroying both surface and ductal P. acnes & also possesses mild comedolytic property.Clindamycin is a lincosamide antibiotic and has antibacterial and anti-inflammatory properties.Adapalene being a third-generation retinoid has comedolytic and anti-inflammatory properties.Second-generation tetracyclines– doxycycline,lymecycline and minocycline–are widely recognized as the first oral antibiotic of choice for the treatment of acne.Doxycycline is a lipophilic tetracycline derivative with demonstrated efficacy in the treatment of inflammatory acne.It is available in doses of 50, 75,100 and 150mg;The most frequently prescribed dose for acne is 100mg.Common adverse effects associated with the use of this combination therapy includes Dry skin, irritative contact dermatitis, skin irritation, skin burning sensation, erythema, skin exfoliation.Based on several studies done across the globe regarding the topical combination therapy used in acne vulgaris, some are effective in decreasing the lesions with well tolerability & none of them proved to be helpful in complete recovery of patients.Hence, this study will be conducted to compare the efficacy, safety and cost effectiveness in moderate to severe facial acne vulgaris.A total of 60 patients visiting skin OPD based on eligibility with inclusion criteria,

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subjects of either gender and subjects of 12 to 30 years of age with moderate to severe facial acne vulgaris having ≥ 19 and ≤38 score based on global acne grading system and after that written informed consent /assent from the subjects will be taken and only then the participants are allowed for a prospective, randomised, open label parallel study for duration of one and a half year at AIIMS Nagpur,will be conducted and Patients will be randomized using computer generated random number table either to receive topical Clindamycin 1% - Adapalene 0.1% combination therapy(0.5 grams applied at night) with oral doxycycline 100mg twice a day or topical Benzoyl peroxide 2.5% - Adapalene 0.1% combination therapy(0.5 grams applied at night)with oral doxycycline 100mg twice a day for 8 weeks and will be followed up at week 4 and 8 and their primary outcomes will be the change in GAGS score from baseline at the end of 8 weeks will be measured by statistical analysis in both groups