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Biotech / Medical : Blueprint Medicines -- Ignore unavailable to you. Want to Upgrade?

To: tuck who wrote (5)	11/15/2018 11:24:05 AM
From: atticus4paws	Read Replies (2) \| Respond to of 12

A week or so ago we got some results in SM that looked good to my untrained eye. I haven't followed BPMC for very long but I wonder if hope in GIST alone has been holding it up in the 60+ range. Does preliminary efficacy in SM count for much at this point? I'm a little under water via some short puts and am considering just taking my loss. Probably a good idea and just hope to be proved wrong.

To: tuck who wrote (5)	11/16/2018 10:39:40 AM
From: tuck	Read Replies (1) \| Respond to of 12

Recall that in 2nd line GIST, BPMC will have to use ctDNA to find the subset for which avapritinib works (apart from the D842V mutation present in 5% of GIST population). From their PR: "analyses of circulating tumor DNA (ctDNA) from the NAVIGATOR trial across all lines showed increased activity for avapritinib in patients without the secondary KIT V654A or T670I mutations, which are estimated to occur in about 20 to 25 percent of GIST patients following treatment with imatinib." So the addressable 2L market is 75% of the total. But . . Detectability of ctDNA for GIST not good You may have to upsize the tweet to see the image, but it is showing GIST ctDNA as detectable in only ~20% of patients (I couldn't find the GIST bar in the publication referenced by the slide, however). A more recent publication found ctDNA in half of pretreated patients (small n, though), which still isn't going to make an oncologist order the test versus prescribing a more broad spectrum drug such as DCPH's. Noninvasive Detection of ctDNA Reveals Intratumor Heterogeneity and Is Associated with Tumor Burden in Gastrointestinal Stromal Tumor Does BPMC have any shot at 2nd line? Cheers, Tuck