Packman, Jeff

ABSTRACT Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare genetic disorder characterized by progressive heterotopic ossification (HO), often heralded by flare-ups, leading to reduced movement and life expectancy. This placebo-controlled, double-blind trial (NCT02190747) evaluated palovarotene, an orally bioavailable selective retinoic acid receptor gamma agonist, for prevention of HO in patients with FOP. Patients experiencing a flare-up were enrolled in two cohorts: (1) patients ≥15 years were randomized 3:1 to palovarotene 10/5 mg (weeks 1–2/3–6) or placebo; (2) patients ≥6 years were randomized 3:3:2 to palovarotene 10/5 mg, palovarotene 5/2.5 mg (weeks 1–2/3–6), or placebo. Cohort data were pooled. The primary endpoint was the proportion of responders (no/minimal new HO at flare-up body region by plain radiograph) at week 6. Change from baseline in HO volume and new HO incidence were assessed by computed tomography (CT) at week 12. Tissue edema was assessed by magnetic resonance imaging (MRI) or ultrasound. Forty patients (aged 7–53 years) were enrolled (placebo: n = 10; palovarotene 5/2.5 mg: n = 9; palovarotene 10/5 mg: n = 21). Disease history was similar between groups. In the per-protocol population, the proportion of responders at week 6 by plain radiograph was 100% with palovarotene 10/5 mg; 88.9% with palovarotene 5/2.5 mg; 88.9% with placebo (Cochran-Armitage trend test: p = 0.17). At week 12, the proportions were 95.0% with palovarotene 10/5 mg; 88.9% with palovarotene 5/2.5 mg; 77.8% with placebo (Cochran-Armitage trend test: p = 0.15). Week 12 least-squares mean (LSmean) new HO volume, assessed by CT, was 3.8 × 103 mm3 with palovarotene 10/5 mg; 1.3 × 103 mm3 with palovarotene 5/2.5 mg; 18.0 × 103 mm3 with placebo (pairwise tests versus placebo: p ≤ 0.12). Palovarotene was well-tolerated. No patients discontinued treatment or required dose reduction; one patient had dose interruption due to elevated lipase. Although these findings were not statistically significant, they support further evaluation of palovarotene for prevention of HO in FOP in larger studies. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Background: ATTR-CM is believed to have a relatively indolent course, with a median survival of ~5 years from heart failure symptoms; however, no data exist as to the rate of progression after disease diagnosis. ATTR-CM is associated with genetic variants, including V122I (present in ~ 3.5% of African Americans), or wild-type TTR (senile systemic amyloidosis - SSA). While there is no effective treatment other than heart transplantation, therapies designed to slow or halt amyloid deposition are in development. The purpose of this study was to characterize the natural history of ATTR-CM to support future therapeutic trials. Methods: Patients with ATTR-CM due to V122I (n = 11) and SSA (n = 18), were enrolled 10.4 ± 11.9 months after diagnosis (range: 0 – 60 months) and assessed every 6 months for up to two years by echocardiography and cardiac magnetic resonance imaging (CMR), with functional capacity assessed by 6-minute walk, and biochemical profile including cardiac troponins and NT-pro-B-type natriuretic peptide (BNP). Baseline data from the full cohort (n = 29), and available data from those completing the 12 month assessment (n = 15) are presented for this on-going study. Results : At baseline, both groups were similar in terms of gender, duration of disease from diagnosis, NYHA, troponin/NT-BNP, and echo or CMR-measured LV wall thickness. SSA patients were older (mean age 76 vs. 71y, P = 0.03), Caucasian (100% vs 0%, P < 0.001), with a history of atrial fibrillation (83% vs. 27%, p = 0.003). During a mean follow-up of 442 days (30–768), there have been 7 deaths (4 V122I; 3 SSA) and 1 cardiac transplantation (SSA), and 10 of 29 (34.5%) were hospitalized at least once (90% for cardiac reasons). For those subjects with a 12 month assessment, LV ejection fraction declined by echo (2.8 %) and CMR (12 %), with minimal changes in wall thickness. Increases were seen in NT-Pro-BNP (87%) and troponin (I: 186%; T: 70%). Worsening of NYHA class occurred in 43% of patients; 6-minute walk distance decreased by 19.2%. Conclusions : Despite reports of a relatively indolent course of ATTR-CM, preliminary data from this ongoing study are the first to demonstrate that quantifiable noninvasive parameters worsen over a 1 year follow up period and are associated with adverse clinical outcomes.