Tetracyline vs clindamycin–rifampicin: which is more effective for hidradenitis suppurativa?

Both tetracycline treatment and clindamycin–rifampicin combination therapy demonstrate significant efficacy after 12 weeks in patients with hidradenitis suppurativa (HS), reports a study. Regardless of disease severity, efficacy does not substantially differ between the two treatments.

“These results might suggest that tetracyclines could be considered as the first-line treatment in patients with moderate-to-severe disease, and failure of tetracyclines may be a sufficient indication for the initiation of biologic therapy,” the researchers said.

This prospective, international cohort study was conducted between October 2018 and August 2019 to examine the 12-week efficacy of oral tetracyclines and a combination of clindamycin and rifampicin. A total of 283 patients were included, of which 63.6 percent were treated with tetracyclines and 36.4 percent with clindamycin and rifampicin.

Both treatments led to a significant reduction in International Hidradenitis Suppurativa Severity Score System from baseline (p<0.001 for both). Some 40.1 percent of patients in the tetracyclines arm and 48.2 percent in the combination therapy achieved the Hidradenitis Suppurativa Clinical Response (HiSCR; p=0.26). [J Am Acad Dermatol 2021;85:369-378]

Of note, neither patient characteristics nor disease severity showed a correlation with the attainment of HiSCR or the minimal clinically important differences for the Dermatology Life Quality Index and pain.

Current guidelines recommend using a combination of clindamycin and rifampicin, but the latter has been shown to markedly reduce plasma concentrations of clindamycin, resulting in a less likely meaningful impact of clindamycin to bacterial resistance or inflammation reduction in this combination. [J Cutan Med Surg 2018;22:71-77; An Bras Dermatol 2019;94:7-19; Br J Dermatol 2019;180:1009-1017; J Am Acad Dermatol 2019;81:91-101; Eur J Dermatol 2014;24:94-95]

A previous study reported similar rates of HiSCR achievement between treatment with clindamycin–rifampicin combination therapy compared with clindamycin alone after 8 weeks (56.7 percent vs 63.3 percent; p=0.598), excluding patients who were lost to follow-up from the efficacy analysis. [J Am Acad Dermatol 2019;80:1314-1321]

“In the current HS treatment guidelines and consensus statements, tetracyclines are considered the first-line treatment for mild-to-moderate HS, whereas the combination of clindamycin and rifampicin is favoured for moderate-to-severe HS,” the researchers said. [J Cutan Med Surg 2018;22:71-77; An Bras Dermatol 2019;94:7-19; Br J Dermatol 2019;180:1009-1017; J Am Acad Dermatol 2019;81:91-101]

Guidelines also advise the initiation of biologics (ie, adalimumab) following failure of conventional treatment, often clindamycin and rifampicin combination therapy.

“However, because our study suggests that this treatment is similar to treatment with tetracyclines, failure of tetracycline treatment could be a sufficient indication for biologic eligibility,” the researchers said. “Nonetheless, a head-to-head randomized, blinded, controlled trial comparing tetracycline treatment with clindamycin and rifampicin combination therapy is needed to increase the evidence to a level where firmer conclusions can be drawn.”

The present study was limited by the exclusion of 23.9 percent and 19.4 percent of patients in the tetracycline and combination therapy arms, respectively, from HiSCR analysis due to a low abscess and nodule count at baseline.