1920P Anlotinib in medullary thyroid carcinoma: A subanalysis based on ALTER01031 study for patients with high prognostic risk

Anlotinib is a multikinase inhibitor that achieved a nearly 2-fold PFS compared with placebo in ALTER01031 (NCT02586350) study for medullary thyroid cancer (MTC). Progressed disease, older age and bone metastasis are generally thought to be negative prognostic factors for thyroid cancer. ALTER01031 study enrolled a large number of pts with these risk factors and this subanalysis explored the outcomes for these pts with or without anlotinib treatment. ALTER01031 was a randomized, placebo-controlled phase IIb trial with the major endpoint of progression-free survival (PFS). Pts enrolled in this study who had progressed disease within 1 year before enrollment (confirmed by medical history recorded or radiographic imaging) or had older age (≥ 50) or diagnosed as bone metastasis were selected to conduct subanaysis. The PFS and overall survival (OS) for these pts were estimated and compared between pts received anlotinib and placebo. 91pts enrolled were randomized to receive anlotinib (62) or placebo (29). The median PFS (mPFS) were 20.67 versus 11.07 months (mo) (P = 0.029). The subanalysis results were summarized in the table below. Pts in placebo arm with high prognostic risk showed poor mPFS. The significant PFS benefits were shown across all subgroups received anlotinib compared with their counterparts who received placebo (P < 0.05). The risk of death was also declined but the difference showed no statistically significance, which may cause by the lack of enough follow-up duration and endpoint events.Table: 1920PNo. of pts with prognostic risk (anlotinib / placebo)mPFS for anlotinib (mo)mPFS for placebo (mo)HR (95% CI) (PFS)P (PFS)mOS for anlotinib (mo)mOS for placebo (mo)HR (95% CI) (OS)P (OS)Progression within 1 year before enrollment (46/22)20.79.10.48 (0.24, 0.95)0.032NENE0.74 (0.29, 1.88)0.520Older age (36/15)17.56.80.31 (0.15, 0.68)0.00228.618.50.62 (0.27, 1.43)0.255Bone metastasis (29/18)20.77.00.44 (0.20, 0.94)0.029NENE0.75 (0.28, 2.01)0.562 Open table in a new tab In ALTER01031, Pts with MTC who has high prognostic risk such as progressed disease, older age or bone metastasis can obtained survival benefits from anlotinib treatment.