A revisit to the tycoon race (MIC Switch) & It’s status quo

Marzuqa Quraishi, Anshul Nigam


The largest portion of pharmaceutical sales comes from chiral drugs, either de novo or by developing them from formerly sold drugs. The economic relevance of these drugs are indicated by the fact that, worldwide sales of chiral drugs reached the figure of more than 300$ billion in 2013. When a drug comprising of two enantiomers (racemates) is substituted by a single purified version of itself (Enantiopure drug), it is called as “Chiral switch”. Most individuals be it patients or physicians are unaware of this term. The switch has its own unique properties making it interesting from a legal standpoint, often found in context of patent expiration and was first exploited by Astra Zeneca over Nexium more than a decade ago. The issue struck headlines of many major newspaper and found its space in scientific journals too. Although, this issue is no more covered by either of them but the practice of patenting pure enantiomers continues to exist and end users (patients) bearing cost of it. Therefore, we have attempted to alarm both researchers and health professionals about the same, explaining enantiomers, their patentability and how the big companies are exploiting it.


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