CStone’s partner Blueprint updated BLU-667 in NSCLC and thyroid cancer, and avapritinib （BLU-285） in gastrointestinal stromal tumors （GIST） at ASCO 2019, showing good progress
Ivosidenib （TIBSOVO） is filed NDA for the treatment of r/r AML in Taiwan, marking the start of commercialization of CStone’s assets
Maintain BUY on the delivery of numerous catalysts
BLU-667and avapritinibdemonstrated potent antitumor effect
Blueprint presented updated data of BLU-667 from the global ARROW study （NCT03037385） at ASCO 2019 regarding RET-fusion+ NSCLC and RET-altered thyroid cancers by oral and poster presentation, respectively. ORR for RET fusion+ NSCLC，MTC and PTC are 56%, 47% and 50%, respectively. Clinical data of avapritinib in 4L+ and PDGFRa Exon 18 GIST from NAVIGATOR study （NCT02508532） were also updated in ASCO. ORR for PDGFRa Exon 18 GIST and 4L+ GIST were 86% and 22%. We believe both BLU-667 and avapritinib exhibit quite solid efficacy data in ASCO this year, which may facilitate their launch process and catalyse their NDA in China.
CStone submitted NDA for TIBSOVO treating r/r AML in Taiwan
A NDA for TIBSOVO for the treatment of r/r AML has been submitted to the Taiwan Food and Drug Administration （TFDA） as the first to-be-approved treatment of CStone. As a first-in-class inhibitor of the mutant isocitrate dehydrogenase-1 （IDH1m inhibitor）， TIBSOVO was granted approval from the U.S. FDA for treating r/r AML in July 2018 based on a Phase I study results （n=174）， including rate and duration of CR and CR with partial hematologic recovery （CRh）， and this NDA filing in Taiwan is very likely to become the first approved treatments for AML patients with IDH1m in the Greater China Area. Updatesfrom CS1001-101 trial inASCO 2019 CStone also presented the updated data from the CS1001-101 trial at ASCO 2019 in a poster presentation （Phase Ia/Ib, NCT03312842）。 Anti-tumor efficacy and safety of CS1001 in patients with advanced solid tumors or lymphomas were similar to those in previous preliminary analysis.
Maintain BUY on the delivery of numerous catalysts
We believe Blueprint’s small molecules demonstrating promising clinical data will accelerate CStone’s NDA in China. Considering the small market size of IDH1m inhibitor in Taiwan, we maintain BUY rating and rNPV-based TP at HK$19.83.