An Evaluation of the Effectiveness of a CBT-Based Digital Therapeutic in Reducing Adolescent Depressive Symptoms

Objectives: Adolescent depression's impact is far-reaching, such as an elevated risk of suicide, comorbidities, and functioning impairments. Engaging mobile technology can enhance treatment adherence, and reduce costs and wait times for mental health care. SparkRx is a 5-week, self-guided, CBT-based digital therapeutic app designed to treat adolescents' depressive symptoms. An RCT (NCT04524598) evaluated SparkRx's clinical effectiveness by comparing SparkRx to a psychoeducation control app (Ctrl). Method(s): A total of 160 eligible adolescents (101 female, aged 13-21 years) with self-reported depressive symptoms were recruited nationwide. They were randomized to use SparkRx or Ctrl for 5 weeks and completed a Patient Health Questionnaire-8 (PHQ-8) weekly. Participants (and caregivers if <18) completed pre- and postintervention assessments. Intention-to-treat analyses (ITT) of all participants with moderate to severe baseline symptom severity (PHQ-8 >=10;N = 121) and per protocol (PP) analyses of only those completing all weekly assessments (N = 83) assessed intervention related depressive symptom changes. We examined engagement with SparkRx (daily active users [DAUs], modules completed and number of mood logs and behavioral activations (BAs) scheduled/completed) and symptom change moderators (gender, baseline severity, concurrent treatment, concurrent treatment changes, age, and ADHD diagnosis). Result(s): SparkRx users had clinically meaningful reductions in depressive symptoms (mu = 5.18 in ITT;mu = 5.98 in PP). ITT (SparkRx vs Ctrl) did not reach statistical significance. PP showed that SparkRx significantly reduced depressive symptoms vs Ctrl (p =.023). SparkRx's median DAUs was 41.95%. On average, SparkRx users completed 63.49% of modules, 19.73 (8.32) mood logs, and 8.71 (5.04) BAs (scheduled 9.86 [5.74]). Mixed linear effects models showed no moderating effects. Conclusion(s): SparkRx was shown to reduce adolescent depressive symptoms and was engaging. Limitations included a sample size that was not fully powered. These claims have not been reviewed by the US FDA with regard to SparkRx's safety or efficacy. In October 2021, Limbix released the initial version of SparkRx under FDA's "Enforcement Policy for Digital Health Devices For Treating Psychiatric Disorders During the Coronavirus Disease 2019 (COVID-19) Public Health Emergency." DDD, ADOL, CBT Copyright © 2022

Persistence of Ad26.COV2.S-associated VITT and specific detection of VITT antibodies

Background: Some COVID-19 vaccinated individuals develop anti-platelet factor 4 (PF4) antibodies that cause thrombocytopenia and thrombosis;a rare syndrome referred to as vaccine-induced immune thrombotic thrombocytopenia (VITT). Currently, information on the characteristics and persistence of anti-PF4 antibodies that cause VITT after Ad26.COV2.S vaccination is limited, and available PF4-polyanion enzyme-linked immunosorbent assays (ELISAs) and functional diagnostic assays fail to differentiate Ad26.COV2.S and ChAdOx1 nCoV-19-associated VITT from similar clinical disorders, namely heparin-induced thrombocytopenia (HIT) and spontaneous HIT. Aim(s): Evaluate the persistence of anti-PF4 antibodies in Ad26. COV2.S-associated VITT and correlate findings with clinical and laboratory variables such as thrombosis and platelet counts. Develop/ investigate laboratory tools that differentiate VITT antibodies from HIT and spontaneous HIT. Method(s): Blood samples from VITT and HIT patient cohorts were tested in antigen-based and functional assays and correlated with clinical and laboratory features. Result(s): While Ad26.COV2.S-associated VITT patients were strongly positive in PF4-polyanion ELISAs;they were frequently negative in the serotonin release assay (4 of 8 tested patients were negative). In contrast, the PF4-dependent p-selectin expression assay (PEA) that uses PF4-treated platelets consistently diagnosed Ad26.COV2.S-associated VITT. Most Ad26.COV2.S-associated VITT antibodies persisted for >5 months in PF4-polyanion ELISAs, while the PEA became negative earlier. Two patients had otherwise unexplained mild persistent thrombocytopenia (140-150,000/ mul) six months after acute presentation. No recurrence of thrombosis was noted. Additionally, a novel un-complexed PF4 ELISA specifically differentiated VITT secondary to Ad26.COV2.S and ChAdOx1 nCoV-19 vaccination, from spontaneous HIT and HIT (Fig 1A-PF4/ polyanion ELISA;Fig 1B-Un-complexed PF4 ELISA;closed black circles-Ad26. COV2.S-associated VITT;closed red circle-ChAdOx1 nCoV-19-associated VITT;***p < 0.001;****p < 0.0001). Its specificity was further confirmed by testing commonly-encountered HIT-suspected patient samples that are PF4/polyanion ELISA-positive but negative in functional assays (1A-1B). Conclusion(s): Ad26.COV2.S-associated VITT antibodies are persistent, and the un-complexed PF4 ELISA appears to be both sensitive and specific for VITT diagnosis.

Deep Vein Thrombosis after COVID-19 Vaccinations

[Formula presented] Background: COVID-19 vaccinations in the United States (Janssen, Moderna, and Pfizer) have been deemed generally safe and effective. Rare thrombotic events, now termed vaccine-induced thrombotic thrombocytopenia (VITT), have been reported after the Janssen and Moderna vaccinations. With millions of vaccinations being administered to adults, it is expected that some deep vein thrombosis (DVT) will occur coincidentally with vaccination. Whether COVID-19 vaccinations may contribute to DVT risk more generally (outside of VITT) has not been well studied outside of the initial clinical trials. Aims: Evaluate trends in DVT diagnosis before and after COVID-19 vaccination Methods: Vaccinated patients ≥ 18 years between 11/6/2020 through 6/1/2021 were analyzed using electronic medical records across the Mayo Clinic enterprise. Upper and lower DVT venous Duplex ultrasound (DUS) reports occurring 90 days before and after vaccination date (first dose for Pfizer and Moderna vaccines) were extracted and analyzed with a highly accurate, previously validated, Natural Language Processing (NLP) algorithm for acute DVT. Results: 382,527 patients with at least 1 COVID-19 vaccination were identified. The median age was 61 (IQR 44-72) and 55.3% were male. Pfizer was the most common vaccine administered (n=245,572, 64.2%), followed by Moderna (n=120,683, 31.6%) and Janssen (n=16,272, 4.3%). Most patients (91.5%) receiving vaccinations were from states with Mayo Clinic health services (Minnesota, n=197,834;Wisconsin, n=80,720;Florida, n=42,391;Arizona, n=28,882). The mean age at vaccination was 61.0 (SD 17.7), 56.5 (SD 19.1), and 54.7 (SD 16.3) for Moderna, Pfizer, and Janssen vaccines respectively. Women were most likely to receive the Pfizer (56.3%) compared to Moderna (54.1%) and Janssen (49.5%) vaccines. Non-white patients were most likely to receive Janssen (21%) compared to Moderna (7.7%) and Pfizer (8.2%) vaccines. Among all patients, 7,265 upper and lower venous DUS were performed in 5,960 patients. Figure 1 shows the utilization of DUS before and after COVID-19 vaccination and shows that more patients underwent DUS in the 90 days after vaccination compared to 90 days pre-vaccination. Acute DVT was identified by the NLP algorithm in 808 (714 patients) ultrasounds (11.1%);656 out of 6136 lower extremity DUS (10.7%) and 152 out of 1129 upper extremity DUS (13.5%). The overall rate of acute DVT (upper and lower) was 1.86 per 1000 patients, consistent with the expected background epidemiologic rate. Figure 2 shows the daily probability of acute DVT by ultrasound report in the 90 days before and after vaccination with a linear regression best fit line showing no overall correlation (R 2 = 0.0). Overall acute DVT post-vaccination occurred on 10.8% of DUS compared to 11.6% pre-vaccination (p=0.28). Among ultrasound reports in Janssen vaccinated patients, 7.0% of post-vaccination compared to 18.0% of pre-vaccination were positive for acute DVT (p=0.003). Among ultrasound reports in Moderna vaccinated patients, 11.0% of post-vaccination compared to 12.7% of pre-vaccination were positive for acute DVT (p=0.15). Among ultrasound reports in Pfizer vaccinated patients, 11.0% of post-vaccination compared to 10.4% of pre-vaccination were positive for acute DVT (p=0.56). Using a Cox proportional hazard model, pre vs post-vaccination time among the same patient cohort was compared for each vaccine. The hazard ratio for DVT post-vaccination was 0.68 (95% CI 0.34-1.38) for Janssen, 1.08 (95% CI 0.86-1.35) for Moderna, and 1.20 (95% CI 0.99-1.46) for Pfizer. After adjusting for age and sex, Pfizer and Janssen's vaccines did not have different risks for DVT compared to Moderna in the 90 days post-vaccination (HR 0.80, 95% CI 0.98-1.25 and HR 0.75, 95% CI 0.42-1.32 respectively). Conclusions: In this large cohort of COVID-19 vaccinated patients, no increased risk for acute DVT post-vaccination was identified for any of the approved vaccinations in the United States. Additionally, no significant difference was seen in the risk f r DVT post-vaccination when comparing each vaccine to each other. The probability of acute DVT on ultrasounds in the 90 days post-vaccination was lower than the pre-vaccination period with the Janssen vaccine possibly indicating over-testing in this group. These results provide additional reassurance of the safety of approved COVID-19 vaccines. [Formula presented] Disclosures: Padmanabhan: Veralox Therapeutics: Membership on an entity's Board of Directors or advisory committees. Pruthi: HEMA Biologics: Honoraria;CSL Behring: Honoraria;Genentech: Honoraria;Instrumentation Laboratory: Honoraria;Bayer Healthcare AG: Honoraria;Merck: Honoraria.

Monoclonal and Oligoclonal Anti-PF4 Antibodies Mediate VITT

Background: ChAdOx1 nCoV-19 (AstraZeneca) and Ad26.COV2.S (Janssen Johnson & Johnson) vaccines against COVID-19 have been associated with thrombotic thrombocytopenic reactions referred to as vaccine-induced immune thrombotic thrombocytopenia (VITT) characterized by the presence of platelet-activating, anti-PF4 antibodies. While VITT shares key clinical features with a similar but separate entity, Heparin-induced thrombocytopenia (HIT), there appear to be important differences: 1) VITT patients have extremely high thrombosis rates and are very strongly positive in PF4-polyanion ELISAs, and 2) Many patients with VITT frequently present with refractoriness to therapy or have disease recurrence that suggests distinct antibody characteristics due to a strong autoimmune anti-PF4 response. Aims: The goal of this study was to characterize anti-PF4 antibodies in VITT. Methods: Five VITT patients were studied, one after ChAdOx1 nCoV-19 vaccination and four after Ad26.COV2. Reactivity of VITT anti-PF4 antibodies to uncomplexed PF4, PF4-Polyvinyl sulfonate (PVS), and PF4-heparin targets was evaluated, and the platelet-activating ability of these antibodies was examined in the PF4-dependent P-selectin Expression assay (PEA). Anti-PF4 antibodies were isolated from patient blood samples using PF4-treated heparin sepharose beads, and isolated antibodies were subject to mass spectrometric evaluation (Liquid Chromatography Electrospray Ionization Quadrupole time-of-flight mass spectrometry [LC-ESI-QTOF MS]). Results: Antibodies from all VITT patients recognized both uncomplexed and complexed PF4 (Fig. 1A). Interestingly, recognition of PF4 by VITT antibodies was lower if PF4 targets were complexed with polyanions, PVS, or heparin (Fig. 1A). These results contrasted with those obtained in a “classical” HIT patient which showed reactivity to PF4/polyanion complexes, but not to uncomplexed PF4 (Fig 1A). All samples activated platelets in the PEA (data not shown). Mass spectrometric evaluation of anti-PF4 antibodies isolated from VITT patients demonstrated monoclonal anti-PF4 antibodies in three patients, and bi- and tri-clonal antibodies in one patient each (a representative monoclonal antibody anti-PF4 antibody is shown in Fig 1B). Consistent with current dogma, polyclonal anti-PF4/polyanion antibodies were seen in “classical” HIT (Fig 1C). Evaluation of anti-PF4 antibodies in spontaneous HIT, a type of autoimmune HIT seen in pro-inflammatory milieus such as orthopedic surgery and infectious prodromes also demonstrated monoclonal anti-PF4 antibodies (Fig 1D). Eluates from control heparin-sepharose beads did not reveal any immunoglobulins (data not shown). Conclusion: Although development of platelet-activating anti-PF4 antibodies and the thrombotic thrombocytopenia syndrome seen after ChAdOx1 nCoV-19 and Ad26.COV2.S vaccination resembles HIT, these findings demonstrate that clonally restricted anti-PF4 antibodies mediate VITT while polyclonal anti-PF4 antibodies mediate HIT. In addition, we noted clonally-restricted anti-PF4 antibodies in another condition that does not require proximate heparin exposure, spontaneous (“autoimmune”) HIT. In VITT, the strong immune response after vaccine administration may result in the activation of a single or few pre-existing anti-PF4 reactive clones, and development of clonally restricted anti-PF4 antibodies with a similar pathophysiology to Spontaneous HIT. It is also likely that high levels of monoclonal/oligoclonal anti-PF4 antibodies cause the severe thrombotic phenotypes seen in VITT and Spontaneous HIT. The high mortality rate and reports of disease refractoriness to therapy in VITT may warrant consideration of additional therapeutic modalities like rituximab and therapeutic plasma exchange in select cases. Figure Legends: (A): VITT (Patient 1-ChAdOx1 nCoV-19;Patients 2-5, Ad26.COV2.S) patient samples were tested in ELISA against uncomplexed PF4 (white), and PF4 in complex with polyvinyl sulfonate (light grey), or unfractionated heparin (dark gray). (B-D) Mass spectrometric evalua ion of anti-PF4 antibodies isolated from VITT (B), HIT (C) and spontaneous HIT patient sera (D). “Relative Intensity” refers to abundance of the Ig light chain relative to the polyclonal background. Numbers above Ig light chain peaks depict mass/charge ratios. NC- Normal control. [Formula presented] Disclosures: Murray: Mayo Clinic: Other: Has received patents for the Mass-Fix technology which has been licensed to the Binding Site with potential royalties. Padmanabhan: Veralox Therapeutics: Membership on an entity's Board of Directors or advisory committees.

Vaccine-Induced Thrombocytopenia and Thrombosis (VITT) Antibodies Recognize Neutrophil-Activating Peptide 2 (NAP2) As Well As Platelet Factor 4 (PF4): Mechanistic and Clinical Implications

VITT is an immune-based complication of adenoviral-based vaccines used to immunize against SARS_CoV2. The antibodies in VITT have been described as directed at the platelet-specific chemokine PF4 (CXCL4). While the clinical course and target chemokine in VITT has much in common with the better-known thrombocytopenic/prothrombotic disorder, heparin-induced thrombocytopenia (HIT), which involves antibodies directed against PF4 bound to the polyanion heparin, the specific loci where VITT and PF4/polyanion HIT antibodies bind appear to differ in studies using alanine-scanning mutations of PF4 (Nature, 2021. DOI: 10.1038/s41586-021-03744-4). The VITT antigenic site localizes to a heparin-binding domain. Unlike the dominant HIT locus, the VITT locus is conserved not only between human and mouse PF4, but also between PF4 and the related platelet-specific chemokine NAP2 (CXCL7). NAP2 is also expressed and stored in platelet alpha-granules and is present in equimolar concentrations to PF4. Unlike PF4, NAP2 avidly binds the chemokine receptor CXCR2 and strongly activates neutrophils. We now show that antibodies from patients who developed VITT after both AstraZeneca (AZ) or Johnson and Johnson (JJ) adenoviral vaccines, unlike HIT antibodies, recognize mouse PF4 (Figure 1A). More importantly, both AZ and JJ VITT antibodies bound NAP2, while none of the HIT antibodies tested bound PF4 or NAP2 in the absence of heparin (Figure 1A). These results are consistent with the alanine-scanning studies that distinguish the HIT and VITT binding sites. Dynamic light scattering (DLS) showed that NAP2 and PF4 bind to the adenoviral vectors, including Ad5 and the AZ vector ChAdOx5, which leads to expression of SARS_CoV2 spike protein. ChAdOx2 vaccine and CsCl 2-purified ChAdOx2 bound to both proteins, but form larger complexes with NAP2 than with PF4 even at lower concentrations of this chemokine (Figure 1C). Removal of anti-PF4 antibodies by hPF4-Sepharose abrogated PF4-dependent binding, but did not significantly reduce binding to NAP2 (not shown), indicating that VITT plasma contains discrete pools of anti-PF4 and anti-NAP2 antibodies that may have distinct functional properties. Sandwich ELISA (not shown) and Western blot analysis of purified VITT IgG demonstrates the presence of hPF4-IgG and NAP2-IgG immune complexes in purified patient's IgG (Figure 2A). Functional studies show that both PF4 and NAP2 can activate platelets in the presence of VITT antibodies. Anti-PF4-depleted VITT IgG fraction retains the ability to activate platelets in the presence of NAP2 (Figure 2B). Thus, unlike HIT, VITT appears to target a shared antigenic site on the related chemokines PF4 and NAP2. This raises the question as to whether NAP2, as one the most abundant platelet chemokines released from activated platelets, is involved in the initiation and propagation of the immunothrombotic response. Additional studies are needed to see whether NAP2, which can potently and specifically activate neutrophils via CXCLR2, contributes to the specific thromboinflammatory phenotype seen in VITT. We propose using FcgammaRIIA+ mice that concurrently express human PF4 and NAP2 and specific knockout of each chemokine, available in our group, to further understand the pathogenesis of VITT and its thrombocytopenic/ prothrombotic phenotype. [Formula presented] Disclosures: Padmanabhan: Veralox Therapeutics: Membership on an entity's Board of Directors or advisory committees. Cines: Dova: Consultancy;Rigel: Consultancy;Treeline: Consultancy;Arch Oncol: Consultancy;Jannsen: Consultancy;Taventa: Consultancy;Principia: Other: Data Safety Monitoring Board.