Tang, Rosa A.

AbstractContextEarly inflammatory thyroid eye disease (TED) can lead to symptomatic chronic disease, including disabling proptosis. Teprotumumab, an insulin-like growth factor-1 receptor (IGF-1R) inhibitor, previously demonstrated efficacy in acute, high-inflammation TED trials.ObjectiveWe present data from the first placebo-controlled trial with teprotumumab in chronic/low disease activity TED.MethodsThis randomized double-masked, placebo-controlled trial, conducted at 11 US centers, enrolled adult participants with TED duration of 2 to 10 years, Clinical Activity Score (CAS) ≤ 1 or no additional inflammation or progression in proptosis/diplopia for ≥1 year, proptosis ≥3 mm from before TED and/or from normal, euthyroid/mildly hypo/hyperthyroid, no prior teprotumumab, and no steroids within 3 weeks of baseline. Patients received (2:1) intravenous teprotumumab or placebo once every 3 weeks (total 8 infusions). The primary endpoint was proptosis (mm) improvement at Week 24. Adverse events (AEs) were assessed.ResultsA total of 62 (42 teprotumumab and 20 placebo) patients were randomized. At Week 24, least squares mean (SE) proptosis improvement was greater with teprotumumab (−2.41 [0.228]) than with placebo (−0.92 [0.323]), difference −1.48 (95% CI −2.28, −0.69; P = .0004). Proportions of patients with AEs were similar between groups. Hyperglycemia was reported in 6 (15%) vs 2 (10%) and hearing impairment in 9 (22%) vs 2 (10%) with teprotumumab and placebo, respectively. AEs led to discontinuation in 1 teprotumumab (left ear conductive hearing loss with congenital anomaly) and 1 placebo patient (infusion-related). There were no deaths.ConclusionTeprotumumab significantly improved proptosis vs placebo in longstanding/low inflammation TED, demonstrating efficacy regardless of disease duration/activity. The safety profile was comparable to that previously reported.

Abstract Disclosure: R.S. Douglas: Consulting Fee; Self; Horizon Therapeutics plc, Immunovant, Viridian. S. Couch: None. S.T. Wester: Advisory Board Member; Self; Horizon Therapeutics plc. Consulting Fee; Self; Immunovant, Sling. B. Fowler: Consulting Fee; Self; Horizon Therapeutics plc. C. Liu: Other; Self; Walter Kluwer Health. P. Subramanian: Consulting Fee; Self; Gensight, Horizon Therapeutics plc, Viridian. R. Tang: Consulting Fee; Self; Viridian, Alexion, Valenza. Research Investigator; Self; Viridian, Horizon Therapeutics plc, Novartis, Immunovant, Vasaragen. Speaker; Self; Serono Speaker Journal Club. Q.T. Nguyen: None. K. Hsu: Employee; Self; Horizon Therapeutics plc. Stock Owner; Self; Horizon Therapeutics plc. M. Karon: Employee; Self; Horizon Therapeutics plc. Stock Owner; Self; Horizon Therapeutics plc. M.N. Stan: Consulting Fee; Self; Immunovant, Horizon Therapeutics plc, Sling, Genentech, ArgenX. Background: Thyroid eye disease (TED) is characterized by expansion of peri- and retro-orbital fat and muscle, often resulting in disfiguring proptosis (eye-bulging) and diplopia (double vision) which may persist chronically. Teprotumumab, an inhibitor of the insulin-like growth factor-1 receptor, demonstrated improvements in proptosis, diplopia, inflammation and quality of life in clinical trials in patients with TED history of short duration (6-13 months), and active disease (clinical activity score [CAS] ≥4). In a published study of 31 patients with CAS≤3 and TED duration >2 years, teprotumumab reduced proptosis, diplopia and inflammation.1 We have undertaken the first randomized, placebo (PBO)-controlled trial to evaluate teprotumumab in patients with chronic/inactive/low CAS TED. The trial has completed randomization with results available in May 2023. Here we report characteristics of the randomized patients. Methods: The trial (NCT04583735) is being conducted in 11 centers in the United States. Key inclusion criteria were age≥18 years, TED duration ≥2 years but <10 years and CAS≤1 in both eyes, ≥3mm proptosis from baseline and/normal for sex and race, or no progression in proptosis or diplopia or new inflammatory symptoms in the preceding year. Patients must have been euthyroid or mildly hypo/hyperthyroid, and not require surgical intervention through the trial. Patients could not have received teprotumumab previously, or steroids within 3 weeks before screening. Patients were randomized 2:1 to receive 8 infusions of teprotumumab (10 mg/kg for the first infusion and 20 mg/kg for the remaining 7 infusions) or PBO once every 3 weeks. The primary endpoint is improvement in proptosis (mm) as compared with PBO from baseline at Week 24. Other endpoints include percentage of proptosis responders (improvement of ≥2mm), diplopia responders (improvement of ≥1 grade in diplopia on the Bahn-Gorman scale, 0-3), and improvement in Graves’ Ophthalmopathy- Quality of Life (GO-QoL), all at Week 24. Adverse events (AE) and AE of special interest will be reported. Results: 62 patients were randomized. 80.6% are female, mean (SD) age was 48.7 (14.94) years. 54.8% are White, 24.2 %, Black or African American, and 12.9%, Asian. Mean (SD) TED duration was 5.2 (1.77) years. 87.1% are never/former smokers. At baseline, mean (SD) proptosis in the study eye was 24.4 (2.94) mm, and mean (SD) CAS was 0.4 (0.49). 27.4% had binocular diplopia with a mean diplopia score of 2. The mean overall GO-QoL score was 63.9 indicating similar disutility as observed in the acute trial population (previously published). Results from this 24-week trial will be presented. Conclusions: Despite a long duration of TED and low “activity”, patients enrolled in this trial have high levels of proptosis and impaired quality of life at baseline. Presentation: Saturday, June 17, 2023

Abstract Disclosure: R.S. Douglas: Consulting Fee; Self; Horizon, Immunovant, Viridian. Research Investigator; Self; Horizon. S. Couch: Research Investigator; Self; Horizon. S.T. Wester: Advisory Board Member; Self; Horizon. Consulting Fee; Self; Immunovant, Sling. Research Investigator; Self; Horizon. B.T. Fowler: Consulting Fee; Self; Horizon. Research Investigator; Self; Horizon. C. Liu: Research Investigator; Self; Horizon. Other; Self; Royalties from Wolters-Kluwer. P. Subramanian: Consulting Fee; Self; Horizon, Gensight, Viridian. Research Investigator; Self; Horizon. R. Tang: Consulting Fee; Self; Viridian, Alexion, Valenza. Research Investigator; Self; Horizon, Viridian, Novartis, Immunovant, Vasaragen. Speaker; Self; Serono Journal Club. Q.T. Nguyen: Research Investigator; Self; Horizon. R.N. Maamari: Research Investigator; Self; Horizon. K. Hsu: Employee; Self; Horizon. Stock Owner; Self; Horizon. M. Karon: Employee; Self; Horizon. Stock Owner; Self; Horizon. M. Stan: Consulting Fee; Self; Septerna Inc, Third Rock Ventures LLC, Genentech, MedicXi Ventures, ArgenX US Inc, Tourmaline Bio, Lassen Therapeutics, Ortho Clinical Diagnostics, Siemens Healthcare, Tolmar Inc, OSE, Immunotherapeutics, Roivant Sciences. Research Investigator; Self; Horizon, Immunovant, ValenzaBio, Sling Therapeutics. Background: Early inflammatory thyroid eye disease (TED) gives way to chronic disease which may lead to long-term disfiguring proptosis (eye-bulging). Teprotumumab, an IGF-1 receptor inhibitor, significantly improved signs and symptoms of newly diagnosed TED (6-13 months) with active disease (clinical activity score [CAS] ≥4) in prior studies. We present data from the first randomized, placebo (PBO)-controlled trial (NCT04583735) with teprotumumab in chronic/low CAS TED, where disease has not regressed. Methods: Pts met all following criteria: ≥18 yrs, TED 2-10 yrs, inactive disease or >1 yr without progression in proptosis/diplopia/new symptoms, baseline (BL) CAS≤1, increased proptosis ≥3mm before TED or from normal, euthyroid/mildly hypo/hyperthyroid, no prior teprotumumab and no steroids within 3 wks of screen. Pts received teprotumumab or PBO once every 3 wks for 21 wks. Primary endpoint was improvement in proptosis(mm) from BL at Wk 24 vs PBO. Secondarily proptosis responders (≥2mm improvement), diplopia responders (≥1 grade improvement on Gorman scale 0-3) with resolved diplopia (grade 0) and improvement in Graves’ Ophthalmopathy-QoL (GO-QoL) visual function (VF) and appearance (AP) subscales were assessed. Treatment-emergent adverse events (TEAE) and AEs of special interest are reported. Study was solely sized/powered for proptosis. Results: 62 pts were randomized 2:1 (ITT, teprotumumab:42; PBO:20), 80.6% were female, mean(SD) age was 48.7(14.94) yrs. Mean(SD) TED duration was 5.2(1.8) yrs. 87.1% were never/former smokers. At BL, mean(SD) proptosis was 24.4(2.94) mm, mean CAS was 0.4, and 29% (teprotumumab, n=14, PBO, n=4) had diplopia with a mean score ∼2. 93%(39) of teprotumumab pts completed the study. At Wk 24, proptosis improvements from BL were significantly greater in the teprotumumab group [2.41 (0.228) mm] vs PBO [0.92(0.323) mm], P<.001. Proptosis response was observed in 26/42 (62%) of teprotumumab pts vs 5/20 (25%) of PBO, P=.01. Diplopia improvement was observed in 6/14 (43%) teprotumumab pts with resolved diplopia in 4(29%) vs 2/4(50%) in PBO and 1(25%) resolved. Significantly greater improvement from BL was observed on GO-QoL-VF for teprotumumab (8.73) vs PBO (2.41), P=.03. Change from BL on AP was 10.03 vs 7.19, P= .65. TEAEs proportions were similar: 33/41(80.5%) of teprotumumab, and 16/20(80%) of PBO pts. Hyperglycemia was reported in 6(15%) vs 2(10%) and hearing impairment in 9(22%) vs 2(10%), respectively. There were two AE discontinuations: teprotumumab (left ear conductive hearing loss with congenital anomaly) and PBO (infusion related). Conclusions: For the first time in pts with longstanding TED and low CAS/inflammation, a medical therapy, teprotumumab, produced significant improvement in proptosis as compared with PBO supporting its use regardless of TED duration or activity. The safety profile was comparable to that previously reported. Presentation: Saturday, June 17, 2023