Rheumatoid Arthritis: Shanahan WR

Maksymowych WP, Blackburn WD, Tami JA, Shanahan WR. · Department of Medicine, University of Alberta, Edmonton, Canada. · J Rheumatol. · Pubmed #11908555 No free full text.

Abstract: OBJECTIVE: To determine the safety of an antisense oligodeoxynucleotide to intercellular adhesion molecule-1 (ICAM-1) (ISIS 2302), administered in an intensive 4 week regimen with dose escalation; and to provide preliminary evidence for efficacy in rheumatoid arthritis (RA). METHODS: Patients with active RA were enrolled in a 6 month, double blind, placebo controlled, dual center, dose escalation (0.5, 1, and 2 mg/kg) study. Subjects received a total of 13 intravenous ISIS 2302 infusions, given on alternate days for 2 weeks and then 3 times a week for another 2 weeks. Doses of corticosteroids (< or = 10 mg/day) and disease modifying antirheumatic drugs (stable > or = 3 months) remained constant throughout the study. The primary efficacy endpoint was the Day 26 Paulus index, with secondary evaluations at Months 2-6. RESULTS: A total of 43 patients were enrolled with 11, 10, 3, and 19 patients receiving placebo or 0.5, 1, or 2 mg/kg of ISIS 2302, respectively. There were no differences between groups after randomization and the mean baseline swollen joint count was 22.5. Pharmacokinetic studies revealed a T(1/2) of 63 min and first-order kinetics with slight dose dependency, suggesting a saturable clearance process, although no accumulation was noted with repeat dosing. The Paulus 20% responses at Day 26 were 20%, 0%, and 5% for patients treated with ISIS 2302 (0.5, 1, 2 mg/kg, respectively) and 36% with placebo. For Months 2-6, the average intent-to-treat Paulus 20% responses were 21.2% for ISIS 2302 and 12.6% for placebo. Only ISIS 2302 treated subjects (19%) achieved Paulus 50% responses. ISIS 2302 was well tolerated. An expected and transient mean activated partial thromboplastin time increase of roughly 7 s was observed at the highest dose (2 mg/kg), as were small and clinically insignificant increases in serum C3a levels. T/B cell immunophenotyping, recall antigen skin testing, and serum immunoglobulin levels revealed no significant immunosuppressive effects. CONCLUSION: This study shows that 13 ISIS 2302 infusions over 4 weeks are well tolerated in patients with active RA. Although significant efficacy was not evident at the primary endpoint (1 month), the study lacked sufficient power to draw any formal conclusions. We tested a 4-fold drug concentration range, which led to a lower area under the curve range than was therapeutic in a subsequent Crohn's disease trial. Any further evaluation of this well tolerated ICAM-1 antisense agent should therefore be conducted at higher dosing.

Shanahan WR. · Isis Pharmaceuticals, Inc., 2292 Faraday Avenue, Carlsbad, California 92008-7208, USA. · Expert Opin Investig Drugs. · Pubmed #15992159 No free full text.

Abstract: ISIS 2302 is a 20 base phosphorothioate oligodeoxynucleotide (ODN) that inhibits intercellular adhesion molecule 1 (ICAM-1) expression through an antisense mechanism. Murine and rat analogues have been effective at doses of 0.06 - 10 mg/kg in a spectrum of models of human inflammatory diseases and allograft transplantation, and ISIS 2302 inhibits the upregulation of ICAM-1 expression in a variety of human cells in vitro. In animals, including primates, plasma distribution half-life ranges from 30 - 60 min, but tissue elimination half-lives range from 1 - 5 days, and the compound is metabolised as other nucleic acids. In a Phase I iv. study, the pharmacokinetic behaviour of ISIS 2302 was similar to that in other primates, and single and multiple every other day doses from 0.06 - 2 mg/kg infused over 2 h were well-tolerated. Phase IIa studies have been completed in Crohn's disease, rheumatoid arthritis, and psoriasis, and a combined Phase I/II renal allograft acute rejection prophylaxis study has just completed enrolment. In these studies, ISIS 2302, 0.5 - 2 mg/kg, or placebo was administered iv. every 2 - 3 days over 14 - 26 days (7 - 13 infusions) to 17 - 52 patients, with follow up for 6 months. In the Crohn's study, evidence of highly durable (5+ month) remission-inducing and steroid-sparing properties were demonstrated, without clinically important adverse events. A 300-patient, pivotal quality trial investigating the steroid-sparing and remission-inducing qualities of ISIS 2302 in patients with steroid-dependent Crohn's disease is completely enrolled, with results expected in the first half of 2000. Modest efficacy and excellent tolerability were demonstrated in the psoriasis and rheumatoid arthritis trials. A Phase IIa trial of a topical formulation in patients with psoriasis is expected to commence in late 1999, as is a trial of an enema formulation in distal ulcerative colitis. Administration by nebulisation for asthma is undergoing preclinical evaluation. Execution of future plans in organ transplantation will await the results of the ongoing Phase I/II trial.