Results from Prioritization of Therapy Uncertainties in Congenital Ichthyosis Study (2015)
Detecting the lack of knowledge with regard to rare disease therapies is particularly important for establishing a research agenda that matches the specific needs of the patient. Therefore, patient participation is a critical element to the research advancement of many studies regarding rare conditions of the skin. In 2014, several affected FIRST members participated in an online survey regarding therapy uncertainties in congenital ichthyosis, excluding ichthyosis vulgaris.
Through this priority-setting study, Dr. Angela Hernández Martín, from Hospital del Niño Jesús in Madrid, was able to identify a top 10 list of the most important therapy uncertainties in ichthyosis. These areas are outlined below in decreasing order of importance:
- Long-term side effects of retinoids: Oral retinoids are widely used and well known to improve congenital ichthyosis. However, some doubts persist about long-term side effects, optimal dosage, and best regimen of therapy (intermittent vs. continuous therapy).
- Best topical keratolytic agent: A variety of topical keratolytic products are available, but there is no clear data favoring one or another, apart from personal preference.
- Itch: Although pruritus is one of the major factors impairing patients’ quality of life, no study has addressed this issue (there are currently studies in process, however no results as of yet.)
- Long-term side effects of topical keratolytic agents: They seem to be beneficial, but concerns about systemic absorption, starting minimum age, maximum daily quantity and body surface, etc., persist.
- Neonatal care - Collodion babies, harlequin ichthyosis: Collodion babies, harlequin ichthyosis babies and patients born with severe ichthyosiform erythroderma show a severe impairment of the cutaneous barrier and often require incubator and infection prophylaxis. Incubator optimal humidity and temperature, best lubricating agent and whether isolating newborns from their mothers is necessary to prevent infections remain to be clarified.
- Best ocular topical treatment: Eye dryness evolving to keratitis and photophobia is a frequent finding regardless the ichthyosis type. Patents use a wide variety of eye drops containing autologous serum, saline solution, hyaluronic acid, etc. with no clear advantage.
- Most effective oral retinoid: Although most ichthyosis patients use acitretin, there are other oral retinoid derivatives such as isotrentinoin, alitretinoin or bexaotene on the market. Whether any of these oral retinoid derivatives is more effacious and has a better security profile is unclear.
- Best treatment to prevent alopecia: Scalp, as well as eyebrow and eyelash hair loss are frequent in many patients with ichthyosis. Scale removal does not seem sufficient to prevent alopecia.
- Role of Gene Therapy: Future curative treatments necessarily involve genetic therapy. Topical targeted therapy has already been assayed with recombinant transglutaminase 1 in humanized skin models in mice, and with topical cholesterol and simvastatin in CHILD syndrome, but studies in humans and /or large patient samples are needed.
- Best Treatment for Erythrodermic forms: Neither topical nor oral keratolytics improve generalized or localized erythema (redness), and perhaps new biologic treatments (as shown in Netherton syndrome), laser therapy, corticosteroids or anti-inflammatory drugs could be useful.
As mentioned in the recent article published in the British Journal of Dermatology, “We are aware that some of the prioritized items are too broad, and that the more concise the uncertainty, the easier to conduct the research. However, these wide areas reflect general important concerns and could be easily transformed into more specific topics and questions.”