DHDavid Hojnacki

David Hojnacki

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Previous Organizations / Institutes

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David Hojnacki has a total of 66 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Post-Partum Clinical and Patient-Reported Outcome Changes in Mothers with Multiple Sclerosis: Findings from the NAPPREMS Study

    by Dejan Jakimovski, Katelyn S. Kavak, Kara Patrick, Omid Mirmosayyeb, Svetlana P. Eckert, David Hojnacki, Bianca Weinstock-Guttman

    Background and Objective: Pregnancy in mothers with multiple sclerosis (MS) commonly results in significant changes in disease activity and changes in clinical care, including the discontinuation of disease modifying therapy (DMT). This study aimed at understanding the clinical and patient-reported outcomes (PROs) before, during and 1-year after delivery. Materials and Methods: A total of 30 pregnant mothers with MS were recruited as part of the study. Clinical (relapse activity and disability changes), PRO information and MRI outcomes were collected on four separate visits: one baseline visit—0–30 days post-delivery; and 3 follow-up visits at week 24, week 36 and week 52 from the baseline. PRO was assessed using a validated questionnaire called the Fatigue Scale for Motor and Cognitive Function (FSMC). The MRI scans were analyzed, and the count of new T2 lesions and/or contrast-enhancing lesions was determined. Results: The average time between delivery and the start of DMT was 142.5 days. Relapse activity before the pregnancy was numerically linked with the activity during the pregnancy, where up to 57.1% of the activity during pregnancy occurred in pwMS with previously active disease before conception (statistically trending with p = 0.073). The relapse activity after the pregnancy occurred twice as often in pwMS whose MS was clinically active before conception. All five pwMS who experienced a relapse prior to the pregnancy experienced worsening in their physical PRO domain. Conclusions: Pre-pregnancy activity is crucial in the screening of mothers with MS at risk for post-partum relapses, worsening of clinical disability and/or PRO measures. A post-partum MS period may benefit from the routine PRO utilization and screening for its worsening. The inflammatory activity during pregnancy was not associated with short-term disease progression.


  • Open Access

    Tixagevimab and Cilgavimab (Evusheld™) Prophylaxis Prevents Breakthrough COVID-19 Infections in Immunosuppressed Population: 6-Month Prospective Study

    by Dejan Jakimovski, Svetlana P. Eckert, Omid Mirmosayyeb, Sangharsha Thapa, Penny Pennington, David Hojnacki, Bianca Weinstock-Guttman

    Background: Persons with neuroinflammatory diseases (pwNID) treated with potent immunosuppressives are at risk of severe COVID-19 outcomes and reduced vaccine seroconversion. We aimed at determining the real-world efficacy of tixagevimab and cilgavimab (Evusheld™) in immunosuppressed pwNID in preventing breakthrough COVID-19 infections. Methods: 31 immunosuppressed pwNID were followed for 6 months after administration of tixagevimab and cilgavimab as a prophylactic COVID-19 medication (January 2022–July 2022). Only pwNID treated with anti-CD20 monoclonal antibodies and sphingosine-1-phosphate modulators were considered eligible for the study. A control group of 126 immunosuppressed pwNID (38 seropositive and 88 seronegative after SARS-CoV-2 vaccination) were included. Breakthrough COVID-19 infections rate and their severity was determined over the follow-up. Results: The pwNID treated with tixagevimab and cilgavimab had more comorbidities when compared with the total and seronegative pwNID control group (54.8% vs. 30.2% vs. 27.3%, p = 0.02 and p = 0.005, respectively). After a 6-month follow-up, significantly lower numbers of pwNID treated with tixagevimab and cilgavimab had breakthrough COVID-19 when compared with the control pwNID group (6.5% vs. 34.1%, p = 0.002) and seronegative control pwNID group (6.5% vs. 38.6%, p < 0.001). All COVID-19 infections in Evusheld-treated pwNID were mild, whereas 9/43 COVID-19 infections in the control group were moderate/severe. No side effects to tixagevimab and cilgavimab were recorded. Conclusion: In pwNID treated with immunosuppressive therapies, tixagevimab and cilgavimab (Evusheld™) significantly reduced the numbers and severity of breakthrough COVID-19 infections during the Omicron (BA.2–BA.5 variants) wave.


  • Open Access

    COVID-19 Vaccination in Multiple Sclerosis and Inflammatory Diseases: Effects from Disease-Modifying Therapy, Long-Term Seroprevalence and Breakthrough Infections

    by Dejan Jakimovski, Karen Zakalik, Samreen Awan, Katelyn S. Kavak, Penny Pennington, David Hojnacki, Channa Kolb, Alexis A. Lizarraga, Svetlana P. Eckert, Rosila Sarrosa, et al.

    Background: To determine the effect of disease-modifying therapies (DMT) on humoral postvaccine seroconversion, long-term humoral response, and breakthrough COVID-19 infections in persons with multiple sclerosis (PwMS) and other neuroinflammatory disorders. Methods: A total of 757 PwMS and other neuroinflammatory disorders were recruited in two MS centers and vaccinated with one of the FDA-approved vaccines (BNT162b2, mRNA-1273, Ad26.COV2.S). The primary outcomes are the rate of humoral postvaccine seroconversion and anti-severe acute respiratory syndrome coronavirus 2 (anti-SARS-CoV-2) immunoglobulin G (IgG) differences between patients on different DMTs. Secondary measures include breakthrough infections and humoral response after six months. Other outcomes include differences in vaccine response between SARS-CoV-2 vaccines and the effects of age and comorbidities on the vaccine response. Results: A total of 465 (68.4%) PwMS and 55 (74.3%) patients with neuroinflammatory diseases were seropositive at 4–12 weeks after vaccination. A significant difference in seroconversion based on the DMT used at the time of vaccination (p < 0.001) was observed, with the lowest rates seen in patients treated with anti-CD20 antibodies (23.2%) and sphingosine-1-phosphate modulators (S1P) (30.8%). In seropositive patients, there was a significant decrease in anti-SARS IgG from mean 20.0 to 4.7 at six months (p = 0.004). Thirty-nine patients had breakthrough infection, but only two seronegative patients required hospitalization. mRNA vaccines resulted in significantly greater seroconversion compared to Ad26.COV2.S (p < 0.001). Older age and presence of cardiovascular comorbidities were associated with lower anti-SARS IgG (p = 0.021 and p = 0.003, respectively) Conclusions: PwMS and neuroinflammatory disorders treated with anti-CD20 and S1P medications have lower humoral response after anti-SARS-CoV-2 vaccination, even after booster dose. Waning of the humoral response puts vaccinated PwMS at a greater risk of COVID-19 breakthrough.


  • Open Access

    Effect of Teriflunomide and Dimethyl Fumarate on Cortical Atrophy and Leptomeningeal Inflammation in Multiple Sclerosis: A Retrospective, Observational, Case-Control Pilot Study

    by Robert Zivadinov, Niels Bergsland, Ellen Carl, Deepa P. Ramasamy, Jesper Hagemeier, Michael G. Dwyer, Alexis A. Lizarraga, Channa Kolb, David Hojnacki, Bianca Weinstock-Guttman

    Background: Pathologic changes in cortical gray matter (GM) and leptomeninges contribute to disability worsening in patients with multiple sclerosis (MS), but there is little evidence whether disease-modifying treatments can slow down cortical pathology in MS. Objectives: To investigate the effect of teriflunomide (TFM) and dimethyl fumarate (DMF) in reducing cortical pathology, as determined by percentage cortical volume change (PCVC) and leptomeningeal contrast enhancement (LMCE) on MRI. Methods: This was a retrospective, single-center, observational study that selected 60 TFM- and 60 DMF-treated MS patients over 24 months. Results: TFM had a lower rate of PCVC compared to DMF over 24 months (−0.2% vs. −2.94%, p = 0.004). Similar results were observed for percentage GM volume change over 0–12 (p = 0.044) and 0–24 (−0.44% vs. −3.12%, p = 0.015) months. No significant differences were found between the TFM and DMF groups in the frequency and number of LMCE foci over the follow-up. TFM showed a numerically lower rate of whole brain atrophy over 24 months (p = 0.077), compared to DMF. No significant clinical or MRI lesion differences between TFM and DMF were detected over follow-up. Conclusions: These findings suggest that TFM has a superior effect on the preservation of cortical GM volume, compared to DMF.


  • Open Access

    Immunological and short-term brain volume changes in relapsing forms of multiple sclerosis treated with interferon beta-1a subcutaneously three times weekly: an open-label two-arm trial

    by Michael G. Dwyer, Robert Zivadinov, Yazhong Tao, Xin Zhang, Cheryl Kennedy, Niels Bergsland, Deepa P. Ramasamy, Jackie Durfee, David Hojnacki, Bianca Weinstock-Guttman, et al.

    Brain volume atrophy is observed in relapsing–remitting multiple sclerosis (RRMS). Brain volume changes were evaluated in 23 patients with RRMS treated with interferon β-1a 44 μg given subcutaneously (SC) three times a week (tiw) and 15 healthy controls. Percentages of whole brain and tissue-specific volume change were measured from baseline (0 months) to 3 months, from 3 to 6 months, and from baseline to 6 months using SIENAX Multi Time Point (SX-MTP) algorithms. Immunological status of patients was also determined and correlations between subsets of T cells and changes in brain volume were assessed. Interferon β-1a 44 μg SC tiw in 23 patients with RRMS resulted in significant reductions in whole brain and gray matter tissue volume early in the treatment course (baseline to 3 months; mean change; –0.95 %; P = 0.030, –1.52 %; P = 0.004, respectively), suggesting a short-term treatment-induced pseudoatrophy effect. From baseline to 6 months, there were significant correlations observed between decreased T- cell expression of IL-17 F and decreased whole brain and brain tissue-specific volume. These findings are consistent with the interpretation of the pseudoatrophy effect as resolution of inflammation following treatment initiation with interferon β-1a 44 μg SC tiw, rather than disease-related tissue loss. ClinicalTrials.gov; NCT01085318


  • Open Access

    Multimodal noninvasive and invasive imaging of extracranial venous abnormalities indicative of CCSVI: Results of the PREMiSe pilot study

    by Robert Zivadinov, Yuval Karmon, Kresimir Dolic, Jesper Hagemeier, Karen Marr, Vesela Valnarov, Cheryl L Kennedy, David Hojnacki, Ellen M Carl, L Nelson Hopkins, et al.

    There is no established noninvasive or invasive diagnostic imaging modality at present that can serve as a ‘gold standard’ or “benchmark” for the detection of the venous anomalies, indicative of chronic cerebrospinal venous insufficiency (CCSVI). We investigated the sensitivity and specificity of 2 invasive vs. 2 noninvasive imaging techniques for the detection of extracranial venous anomalies in the internal jugular veins (IJVs) and azygos vein/vertebral veins (VVs) in patients with multiple sclerosis (MS).


  • Open Access

    Chronic cerebrospinal venous insufficiency is not associated with cognitive impairment in multiple sclerosis

    by Ralph Hb Benedict, Bianca Weinstock-Guttmam, Karen Marr, Vesela Valnarov, Cheryl Kennedy, Ellen Carl, Christina Brooks, David Hojnacki, Robert Zivadinov

    Chronic cerebrospinal venous insufficiency (CCSVI) has been reported in multiple sclerosis (MS) yet its significance in relation to cognitive function is undetermined. This study measured the association between the presence and severity of CCSVI and cognitive impairment in patients with MS. CCSVI was assessed using extra-cranial and trans-cranial Doppler sonography in 109 MS patients (79 with relapsing-remitting, 23 with secondary-progressive and 7 with primary-progressive disease subtype). A subject was considered CCSVI-positive if ≥2 venous hemodynamic criteria were fulfilled. The Minimal Assessment of Cognitive Function in MS (MACFIMS) battery was administered assessing the full spectrum of cognitive domains known to be affected by MS. Depression was quantified using the Beck Depression Inventory Fast Screen (BDIFS). Partial correlations, analysis of variance (or covariance) and linear regression were used to examine the hypothesis that CCSVI status is related to cognition or depression after controlling for education and gender. There were 64 (58.7%) patients who were considered CCSVI-positive. The regression models predicting venous hemodynamic insufficiency severity score were not statistically significant for any of the MACFIMS predictor variables. The analysis of variance tests showed a significant effect of CCSVI-positive diagnosis on cognitive ability in only one of the 10 MACFIMS outcomes, and that one was in the opposite direction of the tested hypothesis. There was no correspondence between CCSVI diagnosis and depression, as measured by the BDIFS. We find no evidence of an association between the presence and severity of CCSVI with cognitive impairment and depression in patients with MS.


  • Open Access

    Comparison of Standard 1.5 T vs. 3 T Optimized Protocols in Patients Treated with Glatiramer Acetate. A Serial MRI Pilot Study

    by Robert Zivadinov, David Hojnacki, Sara Hussein, Niels Bergsland, Ellen Carl, Jacqueline Durfee, Michael G. Dwyer, Cheryl Kennedy, Bianca Weinstock-Guttman

    This study explored the effect of glatiramer acetate (GA, 20 mg) on lesion activity using the 1.5 T standard MRI protocol (single dose gadolinium [Gd] and 5-min delay) or optimized 3 T protocol (triple dose of Gd, 20-min delay and application of an off-resonance saturated magnetization transfer pulse). A 15-month, phase IV, open-label, single-blinded, prospective, observational study included 12 patients with relapsing-remitting multiple sclerosis who underwent serial MRI scans (Days −45, −20, 0; the minus ign indicates the number of days before GA treatment; and on Days 30, 60, 90, 120, 150, 180, 270 and 360 during GA treatment) on 1.5 T and 3 T protocols. Cumulative number and volume of Gd enhancing (Gd-E) and T2 lesions were calculated. At Days −45 and 0, there were higher number (p < 0.01) and volume (p < 0.05) of Gd-E lesions on 3 T optimized compared to 1.5 T standard protocol. However, at 180 and 360 days of the study, no significant differences in total and cumulative number of new Gd-E and T 2 lesions were found between the two protocols. Compared to pre-treatment period, at Days 180 and 360 a significantly greater decrease in the cumulative number of Gd-E lesions (p = 0.03 and 0.021, respectively) was found using the 3 T vs. the 1.5 T protocol (p = NS for both time points). This MRI mechanistic study suggests that GA may exert a greater effect on decreasing lesion activity as measured on 3 T optimized compared to 1.5 T standard protocol.


  • Open Access

    Decreased brain venous vasculature visibility on susceptibility-weighted imaging venography in patients with multiple sclerosis is related to chronic cerebrospinal venous insufficiency

    by Robert Zivadinov, Guy U Poloni, Karen Marr, Claudiu V Schirda, Christopher R Magnano, Ellen Carl, Niels Bergsland, David Hojnacki, Cheryl Kennedy, Clive B Beggs, et al.

    The potential pathogenesis between the presence and severity of chronic cerebrospinal venous insufficiency (CCSVI) and its relation to clinical and imaging outcomes in brain parenchyma of multiple sclerosis (MS) patients has not yet been elucidated. The aim of the study was to investigate the relationship between CCSVI, and altered brain parenchyma venous vasculature visibility (VVV) on susceptibility-weighted imaging (SWI) in patients with MS and in sex- and age-matched healthy controls (HC).


  • Open Access

    Hypoperfusion of brain parenchyma is associated with the severity of chronic cerebrospinal venous insufficiency in patients with multiple sclerosis: a cross-sectional preliminary report

    by Paolo Zamboni, Erica Menegatti, Bianca Weinstock-Guttman, Michael G Dwyer, Claudiu V Schirda, Anna M Malagoni, David Hojnacki, Cheryl Kennedy, Ellen Carl, Niels Bergsland, et al.

    Several studies have reported hypoperfusion of the brain parenchyma in multiple sclerosis (MS) patients. We hypothesized a possible relationship between abnormal perfusion in MS and hampered venous outflow at the extracranial level, a condition possibly associated with MS and known as chronic cerebrospinal venous insufficiency (CCSVI).