of desmosomal proteins. 10 Thus Ca 2+ plays an important role in adhesion between the extracellular domains of desmosomal cadherins 9 and, as tacalcitol has been shown to increase the intracellular concentration of Ca 2+ in cultured keratinocytes, 11 it is possible that calcitriol inhibits acantholysis by increasing the availability of Ca 2+ in the keratinocytes. Our patient failed to respond to topical steroids and anti- biotics, while there was a very good response to calcitriol ointment. This confirms that calcitriol, in common with other vitamin D 3 analogues, may be considered as a therapeutic option for this difficult disease. Department of Dermatology, Royal Liverpool and Broadgreen Hospitals NHS Trust, Liverpool, U.K. E-mail: sanjaysunil@yahoo.com; sanjay.rajpara@nhs.net S.M. R AJPARA C.M. K ING References 1 Burge SM. Hailey–Hailey disease. In: Textbook of Dermatology (Champion RH, Burton JL, Burns DA, Breathnach SM, eds), 6th edn, Vol. 3. Oxford: Blackwell Science, 1998; 1844–7. 2 Aoki T, Hashimoto H, Koseki S. 1a,24-Dihydroxyvitamin D 3 (ta- calcitol) is effective against Hailey–Hailey disease both in vivo and in vitro. Br J Dermatol 1998; 139:897–901. 3 Sand C, Thomsen HK. Topical tacrolimus is effective in the treat- ment of Hailey–Hailey disease—a case report. Arch Dermatol 2003; 139:1401–6. 4 Carlesimo OA, Bottoni U, Bianchi L et al. Attivita ` terapeutica del cal- citriolo nel morbo di Hailey–Hailey. Dermatol Clin 1985; 4:255–63. 5 Kragballe K. Treatment of psoriasis with calcipotriol and other vita- min D analogues. J Am Acad Dermatol 1992; 27:1001–8. 6 Cannata G, Isola PM, Verrini A. Hailey–Hailey disease: local treat- ment with 1a,24-dihydroxyvitamin D 3 . Int J Med Biol Environ 1999; 27:115–17. 7 Korge BP, Smola H, Mauch C et al. Morbus Hailey–Hailey: topical treatment with calcipotriol. HG Z Hautkr 1995; 70:910–12. 8 Delfino M, Cinumino G, Maddaloni M et al. Hailey–Hailey familial pemphigus treated with calcitriol. Ann Ital Dermatol Clin Sper 1990; 44:337–41. 9 Hu Z, Bonifas JM, Beech J et al. Mutations in ATP2C1, encoding a cal- cium pump, cause Hailey–Hailey disease. Nat Genet 2000; 24:61–5. 10 Dhitavat J, Fairclough RJ, Hovnanian A et al. Calcium pumps and keratinocytes: lessons from Darier’s disease and Hailey–Hailey disease. Br J Dermatol 2004; 150:821–8. 11 Hayashi H. Treatment of Grover’s disease with tacalcitol. Clin Exp Dermatol 2002; 27:160–1. Conflicts of interest: none declared. U.S. experience of immunomodulators in the treatment of psoriasis DOI: 10.1111/j.1365-2133.2005.06495.x SIR, I enjoyed the review by Drs Kormeili, Lowe and Yamauchi 1 on the U.S. experience of immunomodulators in psoriasis treatment, but wonder how applicable it is to U.K. practice. The science behind the new biologicals is fascinating, and it is satisfying to see the application of our growing understanding of the pathogenesis of psoriasis applied to develop new treat- ments. Unfortunately, the efficacy of these new agents does not appear to be any greater than that of currently available agents. Comparing different agents without head-to-head studies is an imperfect science, but I have plotted the data for an at least 75% improvement in the Psoriasis Area and Severity Index at 12 weeks in the phase III studies mentioned in the review by Kormeili et al. 2–5 I have then added data drawn from a system- atic review by Spuls et al., giving data for oral retinoids, ciclosporin and psoralen plus ultraviolet (UV) A (PUVA), in which the endpoint plotted is a response of 75–100%, 6 a recent paper using a representative modern methotrexate regimen, 7 and our own Edinburgh data on narrowband UVB. Finally, I have added the gold standard: 3 weeks of inpatient dithranol treatment combined with UVB, where clearance is the end- point. 8 Based on these data (Fig. 1), the efficacy of the biologi- cals in clearing psoriasis appears no better than currently available treatments. The choice of agents used for treating psoriasis is not based on effectiveness at clearing disease alone. Avoidance of side- effects and the monitoring thus required are important, and are frequently emphasized when comparing biologicals with the use of phototherapy and conventional systemic agents. 9 a b Fig 1. (a) Clinical appearance of the right axilla before treatment with calcitriol, showing inflammation, erosions, plaques and crusting. (b) After treatment, the right axilla shows residual hyperpigmentation. Ó 2005 British Association of Dermatologists • British Journal of Dermatology 2005 152, pp803–829 Correspondence 817