Secondary Progressive MS Research Into Natalizumab Continues To Progress

Researchers continue to explore different treatment approaches for secondary progressive MS, ranging from the development of new immunotherapeutic drugs that foster myelin repair and neural protection to immune suppressing drugs that stem the tide of progressive symptoms and advancing debility that typically occurs with the disease. Researchers at the Collaborative MS Research Center at the University of California at San Francisco are working on several different treatment approaches, as well as seeking to develop molecules that may be used as biomarkers to help doctors predict MS progression before it occurs.

However, for those MS patients who have already been diagnosed with secondary progressive MS, the Center’s research into use of the drug Natalizumab may offer particular hope for a definitive treatment for the disease.

The current study involving Natalizumab seeks to determine whether the drug is particularly efficacious in reducing the progression of disability for patients who already have secondary progressive MS. It is a relatively large study involving 156 different site locations throughout the world, and the fact that the study is Phase 3b suggests that the use of the drug in treating SPMS has shown enough success in previous studies to be cleared for testing across a wide range of participants.

The study will use a randomized, double-blind, placebo-controlled approach for approximately 856 SPMS subjects whose disease has clearly progressed to the point where symptoms no long come in waves, but are sustained — the defining feature of secondary progressive MS.  The participants in the study will be randomized to receive either natalizumab 300 mg or placebo intravenously (IV) every 4 weeks (q4wk) for 96 weeks, and participants must be between the ages of 18 and 58, inclusive, with a diagnosis of SPMS for at least 2 years, an EDSS score between 3.0 and 6.5, inclusive, and documented evidence of disease progression independent of clinical relapses over the 1 year prior to enrollment, and who are naïve to Natalizumab.

In point of fact, while Natalizumab may not be commonly known in the MS community — to date, it has generally been used only as a last-resort medication for non-relapsing patients who have tried other drugs to no avail –it is used to treat Crohn’s disease as well. The reason for this is that, while the drug was initially approved by the FDA in 2004, was approved in 2004 after many years of testing, the drug was later linked in three cases of the rare neurological condition progressive multifocal leukoencephalopathy (PML) when administered in combination with interferon beta-1a. Because interferon is typically used as an MS treatment option, the drug was pulled from the market. In this way, Natalizumab has offered middling results, much in the same way that most drugs do during their clinical trials.

The most recent clinical work done on the drug involving secondary progressive MS, however, has been promising. An article in MedScape from 2012 revealed promising results for Natalizumab in progressive MS, with the drug’s Phase 2 study revealing that the drug (this study used the Natalizumab brand Tysabri, from Biogen Idec) reduced inflammation, axonal damage, and demyelination in patients with progressive multiple sclerosis (MS). This was a particularly important study, since inflammation, axonal damage, and myelin repair are all key elements to what will eventually lead to a successful treatment option for secondary progressive MS.

despite the new late-phase study for Natalizumab, the drug undoubtedly has farther to go before it can be claimed as a true breakthrough treatment for SPMS. However, in spite of a few setbacks in testing, the DFA and research community still consider the drug to be a viable option.

Source: BioNews-Tx