Onconova tanks as rigosertib fails in HR-MDS Phase III study

US oncology specialist Onconova (Nasdaq: ONTX) saw its shares decimated after it announced that INSPIRE, the company’s pivotal Phase III study assessing the efficacy and safety of IV rigosertib in higher-risk myelodysplastic syndrome (HR-MDS) patients, did not meet its primary endpoint of improved survival.

The company’s shares slumped 66% by close on Monday and fell a further 6.8% to $0.33 pre-market today.

Expressing disappointment with the results, Dr Steven Fruchtman, president and chief executive, commented: “Onconova is fortunate to have built a product pipeline that includes multiple promising agents, including oral rigosertib and ON 123300. Both compounds target meaningful cancer pathways, and we look forward to further efforts with these programs. The Company will review pipeline and in-licensing opportunities both internally and with external advisors.”