Development of thalidomide-loaded biodegradable devices and evaluation of the effect on inhibition of inflammation and angiogenesis after subcutaneous application

Intravitreal thalidomide ameliorates inflammation in a model of experimental uveitis induced by BCG

Uveitis encompasses a heterogeneous and complex group of conditions characterized by intraocular inflammation, frequently affecting young individuals and representing an important cause of irreversible blindness worldwide. Animal models have been critical to understand etiology and pathogenesis of uveitis, being also employed to assess new therapeutic strategies, preceding human studies. However, there is still a need of developing and studying different models, due to the difficulties in recapitulating all forms of human uveitis effectively. Although corticosteroids are usually the first-line therapy for non-infectious uveitis, their long-term use is limited by potentially serious side effects in all possible delivery routes. Thus, thalidomide, a drug with anti-inflammatory and antiangiogenic properties, was investigated in a novel experimental model of uveitis, induced by Mycobacterium bovis Calmette-Guérin Bacillus (BCG), in rabbits. The experimental protocol consisted of two subcutaneous injections of BCG, followed by two intravitreal injections of the same antigen, inducing panuveitis. Animals were treated with a single intravitreal injection of thalidomide suspension or PBS. Clinical manifestations of uveitis improved after intravitreal thalidomide, involving both anterior and posterior segments. Protein content, N-acetyl-b-glucosaminidase (NAG) and myeloperoxidase (MPO) activities were elevated in ocular tissues after disease induction, further decreasing post-treatment with intravitreal thalidomide. This therapeutic response was also confirmed on ocular electrophysiology, as well as histopathology. This experimental model induced panuveitis in rabbits using a low-cost mycobacterial antigen, with intraocular inflammation subsequently improving after treatment. Intravitreal thalidomide may be a potential alternative to treat intraocular inflammation in corticosteroid-sparing therapies.

Re-bleeding events in patients with small intestinal vascular malformation: Risk factors and effect of treatment with thalidomide

AIM

To investigate the risk factors for re-bleeding events in patients with small intestinal vascular malformation and assess the influence of thalidomide on the re-bleeding rate.

METHODS

This study involved patients with gastrointestinal bleeding referred to the First Affiliated Hospital of Zhengzhou University for capsule endoscopy (CE) and enteroscopy between January 2012 and December 2014. Only patients with small intestinal vascular malformation were included in the study. Follow-up data were obtained through medical records review, telephone interviews or follow-up clinic visits to identify the risk factors associated with re-bleeding. Based on the follow-up data, the re-bleeding rate was compared between patients who had been treated with thalidomide and those who had not.

RESULTS

A total of 156 patients were included in the study, and all of them completed the follow-up, with a mean follow-up duration of 10.78 ± 7.64 mo. Multiple regression analysis identified that presence of hypertension (HR = 1.994, 95%CI: 1.236-3.125, P = 0.005), multiple lesions (≥3) (HR = 1.644, 95%CI: 1.002-2.703, P = 0.049) and liver cirrhosis (HR = 2.116, 95%CI: 1.063-4.212, P = 0.033) were significant independent predictors of re-bleeding, while treatment with thalidomide was a protecting factor (HR = 0.497, 95%CI: 0.303-0.816, P = 0.006). The cumulative re-bleeding rates in patients who were treated with thalidomide and those who were not were 35.71% and 54.65%, respectively, and the difference reached statistical significance (P < 0.05).

CONCLUSION

The re-bleeding rate in patients with small bowel vascular malformation is relatively high, especially those with hypertension, multiple lesions (≥3) and liver cirrhosis. Repeated CE or enteroscopy is recommended for those patients with risk factors for re-bleeding within 2 years. Treatment with thalidomide for patients without contraindication can reduce the re-bleeding rate.