A phase 2 study of anlotinib in patients with metastatic pheochromocytoma/paraganglioma.

Abstract

e15000 Background: Metastatic pheochromocytoma / paraganglioma (MPP) are rare while the prognosis was poor and the efficacy for current therapy was unsatisfactory. Anlotinib is a multikinase inhibitor targeting tumor angiogenesis and growth. Currently, there is no study evaluating the efficacy and safety of anlotinib in MPP pts. Methods: This is a prospective, single-arm phase 2 trial (NCT 04860700). Pts with histologically or radiologically confirmed MPP were enrolled. Main other inclusion criteria were 18-75 years old and ECOG PS 0-2. Anlotinib (8-12mg, QD) were given orally from d1 to d14 every 21 days until disease progression or intolerable toxicities. The primary endpoint was objective response rate (ORR) per RECIST 1.1. Secondary endpoints included biochemical (catecholamine levels) response rate (BRR), progression-free survival (PFS) and safety. Results: 10 pts with MPP were enrolled and tumor response were evaluated in 6 patients. All these 6 patients had objective radiological evidence of progression within 6 months before enrollment. Tumor shrinkage was observed in 4 pts, 1 achieved partial response (PR) and 3 achieved stable disease (SD). The ORR was 16.7% (1/6). For 1 patient (p-1) with no measurable lesions, the pathological lymph nodes shrunk obviously and the rapid progression of bone metastatic lesion was well controlled. Among all 6 pts, catecholamine levels were obviously decreased in 4 pts, achieving a BRR of 67%. 1 patient who developed blindness at right eye caused by the progression of intracranial metastasis after chemotherapy had recovered the vision after anlotinib treatment. At the data cutoff date on February 1st, 2022, 1 patient terminated anlotinib since obvious elevation of catecholamine level and others were still in treatment with no radiographic disease progression. The median treatment duration was 7.5 cycles. The details of efficacy result were listed in table below. Overall, treatment of anlotinib blocked the rapid disease progression and achieved a durable disease control. The most common treatment-related adverse event (TRAE) was hypertension (5/6), which was well controlled, other TRAEs occurred in > 1 pts included grade 1 or 2 proteinuria (2/6) and palmar-plantar erythrodysesthesia syndrome (2/6). Conclusions: The preliminary results of this study indicated that anlotinib is a potential choice for the treatment of MPP with the high ability on disease control and well tolerability. Clinical trial information: NCT04860700. [Table: see text]