A randomized placebo-controlled phase III trial of oral laquinimod for multiple sclerosis.

The phase III placebo-controlled BRAVO study assessed laquinimod effects in patients with relapsing-remitting MS (RRMS), and descriptively compared laquinimod with interferon beta (IFNß)-1a (Avonex(®) reference arm). RRMS patients age 18-55 years with Expanded Disability Status Scale (EDSS) scores of 0-5.5 and documented pre-study relapse (≥ 1 in previous year, 2 in previous 2 years, or 1 in previous 1-2 years and ≥ 1 GdE lesion in the previous year) were randomized (1:1:1) to laquinimod 0.6 mg once-daily, matching oral placebo, or IFNß-1a IM 30 µg once-weekly (rater-blinded design), for 24 months. The primary endpoint was annualized relapse rate (ARR); secondary endpoints included percent brain volume change (PBVC) and 3-month confirmed disability worsening. In all, 1,331 patients were randomized: laquinimod (n = 434), placebo (n = 450), and IFNß-1a (n = 447). ARR was not significantly reduced with laquinimod [-18 %, risk ratio (RR) = 0.82, 95 % CI 0.66-1.02; p = 0.075] vs. placebo. Laquinimod significantly reduced PBVC (28 %, p < 0.001). Confirmed disability worsening was infrequent (10 % laquinimod, 13 % placebo). The change in confirmed disability worsening with laquinimod measured using EDSS was -31 % [hazard ratio (HR) 0.69, p = 0.063], and using Multiple Sclerosis Functional Composite (MSFC) z-score was -77 % (p = 0.150), vs. placebo. IFNß-1a reduced ARR 26 % (RR = 0.74, 95 % CI 0.60-0.92, p = 0.007), showed no effect on PBVC loss (+11 %, p = 0.14), and changes in disability worsening were -26 and -66 % as measured using the EDSS (HR 0.742, p = 0.13) and MSFC (p = 0.208), respectively. Adverse events occurred in 75, 82, and 70 % of laquinimod, IFNß-1a, and placebo patients, respectively. Once-daily oral laquinimod 0.6 mg resulted in statistically nonsignificant reductions in ARR and disability progression, but significant reductions in brain atrophy vs. placebo. Laquinimod was well-tolerated.

Polymorphism in candidate genes: implications for the risk and treatment of idiopathic Parkinson's disease.

Idiopathic Parkinson's disease (IPD) is a progressive neurodegenerative disorder for which no restorative or neuroprotective therapy is available. Interest has recently been directed to association studies on polymorphisms of various genes, mainly those related to dopamine metabolism and transport, and their effect on response to PD, which includes primarily levodopa and dopaminomimetics. Approximately 15-20% of patients with PD do not respond to levodopa, and the majority of those who do respond develop adverse fluctuations in motor response, primarily levodopa-induced dyskinesias. This review summarizes the influence of polymorphisms in various genes on the relative risk of IPD and on levodopa efficacy. It focuses on the importance of well-designed polymorphism studies that include large samples of patients with IPD and tightly matched controls and use identical methodologies. Valid data on such polymorphisms might increase the efficacy of levodopa, decrease its side effects, and reduce the occurrence of levodopa-induced dyskinesias. They might also provide a novel diagnostic tool for PD.

Oxidative stress induced-neurodegenerative diseases: the need for antioxidants that penetrate the blood brain barrier.

Oxidative stress (OS) has been implicated in the pathophysiology of many neurological, particularly neurodegenerative diseases. OS can cause cellular damage and subsequent cell death because the reactive oxygen species (ROS) oxidize vital cellular components such as lipids, proteins, and DNA. Moreover, the brain is exposed throughout life to excitatory amino acids (such as glutamate), whose metabolism produces ROS, thereby promoting excitotoxicity. Antioxidant defense mechanisms include removal of O(2), scavenging of reactive oxygen/nitrogen species or their precursors, inhibition of ROS formation, binding of metal ions needed for the catalysis of ROS generation and up-regulation of endogenous antioxidant defenses. However, since our endogenous antioxidant defenses are not always completely effective, and since exposure to damaging environmental factors is increasing, it seems reasonable to propose that exogenous antioxidants could be very effective in diminishing the cumulative effects of oxidative damage. Antioxidants of widely varying chemical structures have been investigated as potential therapeutic agents. However, the therapeutic use of most of these compounds is limited since they do not cross the blood brain barrier (BBB). Although a few of them have shown limited efficiency in animal models or in small clinical studies, none of the currently available antioxidants have proven efficacious in a large-scale controlled study. Therefore, any novel antioxidant molecules designed as potential neuroprotective treatment in acute or chronic neurological disorders should have the mandatory prerequisite that they can cross the BBB after systemic administration.