What is BG-12?
BG-12 (dimethyl fumarate or DMF) is an experimental oral drug for treating relapsing-remitting multiple sclerosis (RRMS).

Who makes BG-12? 
Biogen that also manufactures Avonex and Tysabri both MS disease modifying drugs.

Is BG-12 new?
DMF used for for MS treatment would be a new. DMF is a Fumaric Acid Ester (FAE) and has been used in the treatment of psoriasis since 1959. Since 1994, DMF has been sold in Germany under the name Fumaderm for psoriasis treatment.

Is the drug approved? 
BG-12 has been submitted to the US Food & Drug Administration, European Union, Canada and Switzerland for approval. The drug was submitted to the US FDA on February 28th and has been granted "fast track" status. The US FDA BG-12 ruling should come out between Q3 2012 and Q1 2013. 

How does the drug work?
Immunomodulatory: BG-12 is thought to help regulate the immune system by changing the immune response. 
Neuroprotective: BG-12 partially protects the blood brain barrier and enchances myelin repair.
Anti-inflammatory: BG-12 is thought to decrease central nervous system inflammation.

How is BG-12 administered?
BG-12 is an oral medication that has been tested taken 2 or 3 (BID or TID) times/day.

What BG-12 MS trial have been conducted?
Two Phase III studies have been conducted with names "DEFINE" and "CONFIRM" both having over 1,000 patients

What were the trial results?

Taken twice daily (BID)
53% annual reduction in relapse rate
44% relapse rate reduction at 24 months
21% reduction in disease progression
38% reduction in disability progression
85% reduction in the mean number of new or newly enlarging T2 hyperintense lesions
90% reduction in galadium enhancing lesions
72% reduction in T1 hypointense lesions

Taken thrice daily (TID)
48% annual reduction in relapse rate
51% relapse rate reduction at 24 months
24% reduction in disease progression
34% reduction in disability progression
74% reduction in the mean number of new or newly enlarging T2 hyperintense lesions
73% reduction in galadium enchanging lesions
63% reduction in T1 hypointense lesions

What about side effects?

The serious or adverse events for patients on BG-12 and placebo were statistically similar. 

Common side effects have been:
Flushing in 38% of BID and 32% of TID patients
Upset stomach, diarrhea, nausea and abdominal pain
Headache

The studies revealed a decrease in side effects for most patients after one month on therapy. Fumaderm users have noted similar side effect reductions after increased use.

What will BG-12 cost?
Biogen hasn't released this information, but BG-12 will probably be in-line with other MS therapies (expensive).