Successful use of thalidomide for refractory esophageal Crohn's disease

Thalidomide and its analogues: A review of the potential for immunomodulation of fibrosis diseases and opthalmopathy

The US Food and Drug Administration approved thalidomide and its analogues for the treatment of erythema nodosum leprosum, in spite of the notoriety of reports of severe birth defects in the middle of the last century. As immunomodulatory drugs, thalidomide and its analogues have been used to effectively treat various diseases. In the present review, preclinical data about the effects of thalidomide and its analogues on the immune system are integrated, including the effects of cytokines on transdifferentiation, the anti-inflammatory effect, immune cell function regulation and angiogenesis. The present review also investigates the latest developments of thalidomide as a therapeutic option for the treatment of idiopathic pulmonary fibrosis, skin fibrosis, and ophthalmopathies.

The Dihydroxy Metabolite of the Teratogen Thalidomide Causes Oxidative DNA Damage

Thalidomide [α-(N-phthalimido)glutarimide] (1) is a sedative and antiemetic drug originally introduced into the clinic in the 1950s for the treatment of morning sickness. Although marketed as entirely safe, more than 10 000 babies were born with severe birth defects. Thalidomide was banned and subsequently approved for the treatment of multiple myeloma and complications associated with leprosy. Although known for more than 5 decades, the mechanism of teratogenicity remains to be conclusively understood. Various theories have been proposed in the literature including DNA damage and ROS and inhibition of angiogenesis and cereblon. All of the theories have their merits and limitations. Although the recently proposed cereblon theory has gained wide acceptance, it fails to explain the metabolism and low-dose requirement reported by a number of groups. Recently, we have provided convincing structural evidence in support of the presence of arene oxide and the quinone-reactive intermediates. However, the ability of these reactive intermediates to impart toxicity/teratogenicity needs investigation. Herein we report that the oxidative metabolite of thalidomide, dihydroxythalidomide, is responsible for generating ROS and causing DNA damage. We show, using cell lines, the formation of comet (DNA damage) and ROS. Using DNA-cleavage assays, we also show that catalase, radical scavengers, and desferal are capable of inhibiting DNA damage. A mechanism of teratogenicity is proposed that not only explains the DNA-damaging property but also the metabolism, low concentration, and species-specificity requirements of thalidomide.

Tofacitinib for the treatment of tumor necrosis factor-α inhibitor refractory esophageal Crohn's disease: a case report

BACKGROUND

Esophageal Crohn's disease is reported as a rare manifestation, although its prevalence may be underestimated because upper endoscopies are not routinely performed in asymptomatic adults. Tofacitinib, an oral janus kinase inhibitor, is a new biologic that has shown promise in the treatment of ulcerative colitis and may be effective in the treatment of Crohn's disease according to phase 2 trials. We report the first case of esophageal Crohn's disease successfully treated with tofacitinib in a patient with worsening symptoms despite maintenance therapy with a tumor necrosis factor-α inhibitor.

CASE PRESENTATION

A 67-year-old Caucasian woman presented with new dysphagia and had findings of esophageal Crohn's disease on endoscopy. The dosage of her current biologic therapy-adalimumab-was increased in frequency, without improvement. Our patient was started on tofacitinib and demonstrated an improvement in symptoms, with a repeat endoscopy showing resolution of the previous lesions.

CONCLUSION

Esophageal Crohn's disease is likely underdiagnosed but is an important consideration in a patient with new symptoms of dysphagia and known Crohn's disease. Tofacitinib, while a novel agent, could have a role in the treatment of esophageal Crohn's disease that does not improve with intensification of the current biologic therapy. It provides a different mechanism in patients who become refractory to maintenance therapy.

Thalidomide induces mucosal healing in postoperative Crohn disease endoscopic recurrence: Case report and literature review

BACKGROUND

Thalidomide has been successful use in patients with refractory Crohn disease (CD) in recent years.

METHODS

We collected the data of a postoperative CD patient who was prescribed thalidomide to induce remission and reviewed the relevant literatures.

RESULTS

A 51-year-old female was diagnosed as CD after an urgent terminal intestinal resection and presented endoscopic recurrence despite the prophylactic treatment with azathioprine (AZA). Fortunately, she achieved mucosal healing (MH) at a low dose of thalidomide for 15 months.

CONCLUSION

Thalidomide is effective to induce MH in the postoperative CD endoscopic recurrence.

Ustekinumab for Successful Treatment of Refractory Esophageal Crohn's Disease

Esophageal involvement in Crohn’s disease is rare. We present a case of refractory esophageal Crohn’s disease that responded to ustekinumab, which has shown promise in the treatment of refractory, typically intestinal Crohn’s disease. There are no prior reports on the successful use of ustekinumab in esophageal Crohn’s disease, but should be considered as a possible management strategy in patients with this condition.

The clinical implications of thalidomide in inflammatory bowel diseases

Thalidomide has anti-inflammatory and anti-angiogenetic activity that makes it suitable for treating inflammatory bowel diseases (IBD). The recent guidelines from the European Crohn's and Colitis Organization/European Society for Pediatric Gastroenterology Hepatology and Nutrition conclude that thalidomide cannot be recommended in refractory pediatric Crohn's disease but that it may be considered in selected cohorts of patients who are not anti-TNFα agent responders. The main adverse effect is the potential teratogenicity that renders the long-term use of thalidomide problematic in young adults due to the strict need for contraceptive use. In short-term use it is relatively safe; the most likely adverse effect is the neuropathy, which is highly reversible in children. So far the use of thalidomide is reported in 223 adult and pediatric IBD patients (206 with Crohn's disease). In the following sections, the authors will discuss efficacy and safety of thalidomide, in the short-term treatment of IBD.

Human cytochrome P450 oxidation of 5-hydroxythalidomide and pomalidomide, an amino analogue of thalidomide

The sedative and antiemetic drug thalidomide [α-(N-phthalimido)glutarimide] was withdrawn in the early 1960s because of its potent teratogenic effects but was approved for the treatment of lesions associated with leprosy in 1998 and multiple myeloma in 2006. The mechanism of teratogenicity of thalidomide still remains unclear, but it is well-established that metabolism of thalidomide is important for both teratogenicity and cancer treatment outcome. Thalidomide is oxidized by various cytochrome P450 (P450) enzymes, the major one being P450 2C19, to 5-hydroxy-, 5'-hydroxy-, and dihydroxythalidomide. We previously reported that P450 3A4 oxidizes thalidomide to the 5-hydroxy and dihydroxy metabolites, with the second oxidation step involving a reactive intermediate, possibly an arene oxide, that can be trapped by glutathione (GSH) to GSH adducts. We now show that the dihydroxythalidomide metabolite can be further oxidized to a quinone intermediate. Human P450s 2J2, 2C18, and 4A11 were also found to oxidize 5-hydroxythalidomide to dihydroxy products. Unlike P450s 2C19 and 3A4, neither P450 2J2, 2C18, nor 4A11 oxidized thalidomide itself. A recently approved amino analogue of thalidomide, pomalidomide (CC-4047, Actimid), was also oxidized by human liver microsomes and P450s 2C19, 3A4, and 2J2 to the corresponding phthalimide ring-hydroxylated product.