Morris, John C.

AbstractBackgroundRapidly progressive dementia (RPD) is variably defined across published cohorts. A standardized definition is needed to support multicenter studies required to inform the causes of RPD and optimize recognition and management of treatment‐responsive causes. An optimal definition will capture the broad spectrum of causes of RPD, adequately differentiate patients with rapid and typically progressive presentations of neurodegenerative disease, and be reliably implemented across healthcare settings and centers.MethodThe Clinical Dementia Rating® (CDR) is a validated dementia staging tool that is widely used in clinical trials and observational studies. We applied the CDR to diagnose RPD in patients who developed dementia (CDR ≥1) within 1 year or incapacitation (CDR ≥2) within 2 years of symptom onset. This definition was prospectively applied to patients with suspected RPD at Mayo Clinic in Florida (MCF: Jacksonville, FL; Jan 2020 – Oct 2023) and Washington University in St. Louis (WU: Saint Louis, MO; Jun 2016 – Dec 2019), and retrospectively applied to individuals within the National Alzheimer’s Coordinating Center (NACC) dataset. Criteria performance was compared across cohorts.ResultTwo‐hundred twenty‐six patients were referred with suspected RPD at MCF‐WU. Of these, 155/226 (68.6%) met our proposed RPD criteria, including patients with Alzheimer disease and related dementias (ADRD; 34/155, 21.9%), Creutzfeldt Jacob disease (CJD; 25/155, 16.1%), autoimmune encephalitis (52/155, 33.5%), vascular pathologies (14/155, 9.0%), toxic/metabolic disruptions (7/155, 4.5%) and primary psychiatric disorders (4/155, 2.6%). A small subset of NACC participants met our proposed RPD criteria (836/20,418; 0.04%), emphasizing the unique nature of RPD. Causes of RPD in NACC included ADRD (676/836, 80.1%), CJD (72/836, 8.6%), and vascular pathologies (24/836, 2.9%). Rates of progression (∆CDR sum‐of‐boxes/year) clearly distinguished patients with RPD from non‐RPD in both cohorts (MCF‐WU, 13.6±5.8 vs 4.7±5.9, p<0.001; NACC, 6.7±3.1 vs. 1.7±1.4, p<0.001).ConclusionOur CDR‐based definition of RPD distinguished patients with a broad spectrum of causes of RPD from those with typically progressive dementia across multiple cohorts. Broad application of this criteria would standardize diagnosis of RPD and support the design and implementation of multicenter studies RPD.

Abstract Background The overall survival of patients with advanced thyroid cancers that have progressed following targeted therapies is limited, indicating a strong need for salvage treatments. Methods We retrospectively analyzed patients with refractory advanced thyroid cancer treated with pemetrexed‐carboplatin (PC) at Mayo Clinic since 2019. Results Eleven patients, three with anaplastic thyroid cancer (ATC), seven with differentiated or poorly differentiated thyroid cancer (DTC), and one with oncocytic carcinoma of the thyroid, were treated with novel salvage PC. Patients with DTC ( n = 7) had durable responses with a median progression‐free survival of 29 months. One responder included a patient with ATC whose disease progressed following pembrolizumab/axitinib, lenvatinib, and dabrafenib/trametinib. On this fourth line treatment, the patient remains on therapy to date, over 12 months after initial response. Conclusions This case series reinforces prior published phase I clinical trial data and shows that pemetrexed can have potent efficacy in the treatment of the most advanced thyroid cancers.

Abstract Context Metastatic pheochromocytomas and paragangliomas (mPPGL) are rare vascular neuroendocrine tumors that highly express vascular growth factors. Systemic treatment options in cases of unresectable multisite disease are limited. Multikinase inhibitors that inhibit angiogenesis, such as lenvatinib, have proven effective in several other malignancies, and may be a viable option for mPPGL. Objective We aimed to evaluate the efficacy of lenvatinib as salvage therapy in mPPGLs. Methods This was a retrospective analysis of mPPGL patients ≥ 18 years of age who received lenvatinib from 2015 to 2020 at a tertiary referral center. Patients were started on lenvatinib 20 mg daily and dose was adjusted according to tolerance or disease progression. Results Eleven patients were included. Median treatment duration was 14.7 months (95% CI, 2.3-NE). Treatment was discontinued due to disease progression, adverse events, or death. Overall survival at 12 months was 80.8% (95% CI, 42.3-94.9%) but its median was not reached. Median progression-free survival was 14.7 months (95% CI, 1.7-NE). Among the 8 patients with measurable disease, overall response rate was 63%, as 5/8 experienced a partial response and 3/8 had stable disease. Worsening hypertension and anemia were the most common adverse events. Conclusion Lenvatinib may be a viable treatment option for mPPGL, although at the potential risk of worsening hypertension. Larger, multicenter studies are needed to better characterize treatment efficacy.

11006 Background: CMB305 is an active immunotherapy regimen designed to generate and expand anti-NY-ESO-1 T cells. It consists of LV305, a dendritic cell targeting lentiviral vector encoding NY-ESO-1, and a boost with G305, an NY-ESO-1 recombinant protein plus GLA-SE, a TLR-4 agonist. An LV305 phase 1 study demonstrated a 1-yr survival of 81% and induction of anti-NY-ESO-1 T cells in sarcoma patients (pts). This first-in-human study of CMB305 examined safety, immunogenicity, and efficacy in pts with NY-ESO-1 positive (+) solid tumors. Methods: Adults with previously treated NY-ESO-1+ sarcomas, NSCLC, ovarian cancer were enrolled in a 3+3 dose-escalation with an expansion phase 1 study. The CMB305 regimen included 4 intradermal injections of LV305 at 109 or 1010 vector genomes, alternating with 3 intramuscular G305 injections at 250 µg for 3 months, then bimonthly G305 injections up to 1 yr. Results: As of 31Dec2016, 25 pts with STS (15 synovial (SS), 8 myxoid/round cell liposarcoma (MRCL), 2 other) were evaluable for safety; 23 SS/MRCL pts were evaluable for immune response (IR) and efficacy. All SS and MRCL pts received prior therapy for locally advanced/metastatic disease, 67% > = 2 prior chemo regimens. No DLTs were observed; treatment related AEs were grade 1 and 2, except 1 pt with grade 3 SAE (prostatic pain). Of 11 SS/MRCL pts tested, 64% pts developed NY-ESO-1 specific T cells and 72% pts anti-NY-ESO-1 antibodies. T cell receptor sequencing indicated increased clonality, and antigen spreading after CMB305. Best response by immune related response criteria was stable disease in 8/15 (53%) SS pts and 6/8 (75%) MRCL pts. The 3 month PFS rate was 74% and 75% for SS and MRCL pts. Median survival has not been reached with 1-yr survival rate of 86% and 100% for SS and MRCL pts. Conclusions: CMB305 is safe, well tolerated, and demonstrates a survival rate that is favorable when compared with approved agents for recurrent STS. CMB305 resulted in a stronger and broader integrated IR than LV305, including antigen spreading. These data warrant further investigation of CMB305 as a monotherapy in a randomized clinical study in STS. A randomized study of CMB305 in combination with atezolizumab in SS/MRCL pts is ongoing. Clinical trial information: NCT02387125.

3090 Background: The correlation of immune response (IR) and clinical benefit in patients (pts) who receive active immunotherapy remains controversial. CMB305 is an active immunotherapy designed to generate and expand anti-NY-ESO-1 T cells, consisting of LV305 (a DC targeting lentiviral vector encoding NY-ESO-1) and a boost (NY-ESO-1 recombinant protein plus GLA-SE, a TLR-4 agonist). Phase 1 studies of LV305 and CMB305 evaluated the IR and survival of pts with NY-ESO-1 positive tumors. Methods: 62 pts with recurrent NY-ESO-1 expressing (by IHC) solid tumors were enrolled in 2 Phase 1 trials (31 pts each: 43 sarcomas, 12 ovarian, 4 melanomas, and 3 NSCLC). Peripheral blood was assessed pre and post therapy for anti-NY-ESO-1 T cell responses (IFNγ ELISPOT) and antibodies (Ab) (ELISA) (n = 62), TCR-β CDR3 repertoire and conserved (public) TCR (n = 28), and antigen spreading (ELISA, ELISPOT) (n = 23). Relationship between progression-free survival (PFS), overall survival (OS) and up to 15 biomarkers were analyzed by the Kaplan-Meier method. Results: Preexisting anti-NY-ESO-1 T cells and Ab were identified in 34% and 40% of pts. LV305 and CMB305 induced (de novo or increased) anti-NY-ESO-1 T-cells in 51% and 65% pts, and anti-NY-ESO-1 Ab responses in 13% and 68% pts, respectively. LV305 and CMB305 induced antigen spreading in 17% and 36% pts. TCR clonality increased after CMB305 as compared to LV305. The TCRβ-CDR3 amino acid sequences of three NY-ESO-1 specific TCR clones in a patient with a > 2-year response were fully conserved in 20/28 patients. Biomarkers showing the strongest association with OS and PFS were pre-existing anti-NY-ESO-1 T-cell response and Ab, integrated IR (T cells and antibodies), and NY-ESO-1 expression level. Presence of public TCRs was associated with longer survival, particularly in pts with high ( > 50%) NY-ESO-1 expression. Conclusions: While LV305 and CMB305 are both immunogenic, CMB305 resulted in a stronger and broader integrated IR, including antigen spreading. The three identified survival variables, preexisting and treatment-induced NY-ESO-1 IR and the presence of public TCRs, warrant validation in randomized studies of CMB305.