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Dive into the research topics where Zoran Popmihajlov is active.

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Featured researches published by Zoran Popmihajlov.


The Journal of Infectious Diseases | 2016

Cellular and Humoral Responses to a Second Dose of Herpes Zoster Vaccine Administered 10 Years After the First Dose Among Older Adults

Myron J. Levin; Kenneth E. Schmader; Lei Pang; Angela Williams-Diaz; Gary O. Zerbe; Jennifer Canniff; Michael Johnson; Yupanqui Caldas; Alice Cho; Nancy Lang; Shu-Chih Su; Janie Parrino; Zoran Popmihajlov; Adriana Weinberg

BACKGROUND Herpes zoster vaccine (ZV) was administered as a second dose to 200 participants ≥ 70 years old who had received a dose of ZV ≥ 10 years previously (NCT01245751). METHODS Varicella zoster virus (VZV) antibody titers (measured by a VZV glycoprotein-based enzyme-linked immunosorbent assay [gpELISA]) and levels of interferon γ (IFN-γ) and interleukin 2 (IL-2; markers of VZV-specific cell-mediated immunity [CMI], measured by means of ELISPOT analysis) in individuals aged ≥ 70 years who received a booster dose of ZV were compared to responses of 100 participants aged 50-59 years, 100 aged 60-69 years, and 200 aged ≥ 70 years who received their first dose of ZV. The study was powered to demonstrate noninferiority of the VZV antibody response at 6 weeks in the booster-dose group, compared with the age-matched first-dose group. RESULTS Antibody responses were similar at baseline and after vaccination across all age and treatment groups. Both baseline and postvaccination VZV-specific CMI were lower in the older age groups. Peak gpELISA titers and their fold rise from baseline generally correlated with higher baseline and postvaccination VZV-specific CMI. IFN-γ and IL-2 results for subjects ≥ 70 years old were significantly higher at baseline and after vaccination in the booster-dose group, compared with the first-dose group, indicating that a residual effect of ZV on VZV-specific CMI persisted for ≥ 10 years and was enhanced by the booster dose. CONCLUSIONS These findings support further investigation of ZV administration in early versus later age and of booster doses for elderly individuals at an appropriate interval after initial immunization against HZ. CLINICAL TRIALS REGISTRATION NCT01245751.


Vaccine | 2017

Herpes zoster vaccine live: A 10 year review of post-marketing safety experience

English Willis; Meredith Woodward; Elizabeth Brown; Zoran Popmihajlov; Patricia Saddier; Paula W. Annunziato; Neal A. Halsey; Anne A. Gershon

BACKGROUND Zoster vaccine is a single dose live, attenuated vaccine (ZVL) indicated for individuals ≥50 years-old for the prevention of herpes zoster (HZ). Safety data from clinical trials and post-licensure studies provided reassurance that ZVL is generally safe and well tolerated. The objective of this review was to provide worldwide post-marketing safety information following 10 years of use and >34 million doses distributed. METHODS All post-marketing adverse experience (AE) reports received worldwide between 02-May-2006 and 01-May-2016 from healthcare professionals following vaccination with ZVL and submitted to the MSD AE global safety database, were analyzed. RESULTS A total of 23,556 AE reports, 93% non-serious, were reported. Local injection site reactions (ISRs), with a median time-to-onset of 2 days, were the most frequently reported AEs followed by HZ. The majority of HZ reports were reported within 2 weeks of vaccination and considered, based on time-to-onset, pathogenesis of HZ, and data from clinical trials, to be caused by wild-type varicella-zoster virus (VZV). HZ confirmed by PCR analysis to be VZV Oka/Merck vaccine-strain was identified in an immunocompetent individual 8 months postvaccination and in 4 immunocompromised individuals. Disseminated HZ was reported very rarely (<1%) with 38% occurring in immunocompromised individuals. All reports of disseminated HZ confirmed by PCR as VZV Oka/Merck vaccine-strain were in individuals with immunosuppressive conditions and/or therapy at the time of vaccination. CONCLUSIONS The safety profile of ZVL, following 10 years of post-marketing use, was favorable and consistent with that observed in clinical trials and post-licensure studies.


Clinical Infectious Diseases | 2017

Safety and Immunogenicity of Inactivated Varicella-Zoster Virus Vaccine in Adults With Autoimmune Disease: A Phase 2, Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Michael Eberhardson; Stephen D. Hall; Kim A Papp; Tina M. Sterling; Jon E. Stek; Lei Pang; Yanli Zhao; Janie Parrino; Zoran Popmihajlov

Background Immunogenicity and safety of inactivated zoster vaccine (ZVIN) were evaluated in adults with autoimmune disease. Methods Adults with autoimmune disease treated with immunosuppressive therapy (biologic or nonbiologic) were randomized to receive 4 doses of ZVIN, ZVIN containing a higher quantity of antigen, or placebo. To measure varicella-zoster virus (VZV)-specific immune responses using glycoprotein enzyme-linked immunosorbent assay (gpELISA) and interferon-gamma enzyme-linked immunospot (IFN-γ ELISPOT), blood samples were collected at baseline, post-doses 2, 3, and 4. The primary hypothesis was that ZVIN would elicit significant VZV-specific immune responses, measured by gpELISA or ELISPOT, at approximately 28 days post-dose 4. Safety and tolerability was assessed through 28 days post-dose 4. Results ZVIN elicited a statistically significant VZV-specific immune response approximately 28 days post-dose 4, measured by gpELISA (estimated geometric mean fold rise from baseline [GMFR] = 1.6 [95% confidence interval [CI], 1.4,1.7], P value < .0001) and IFN-γ ELISPOT (estimated GMFR = 2.0 [95% CI, 1.6,2.6], P value < .0001); both results met the prespecified success criterion. Overall, 57% (164/289) of all ZVIN and 21% (13/62) of placebo recipients reported ≥1 injection-site adverse events (AEs), and 52% (149/289) and 47% (29/62) reported ≥1 systemic AEs, respectively. Eight ZVIN and 1 placebo recipients experienced serious AEs, including 2 events (ZVIN group) determined by the investigator to be vaccine related (keratitis; amnesia). Overall frequency of AEs decreased with subsequent doses of vaccine. Conclusions In adults with autoimmune disease, ZVIN was well tolerated and elicited statistically significant VZV-specific immune responses approximately 28 days post-dose 4, measured by gpELISA and IFN-γ ELISPOT. Clinical Trials Registration NCT01527383.


Scandinavian Journal of Pain | 2016

Osteoarthritis patients with pain improvement are highly likely to also have improved quality of life and functioning. A post hoc analysis of a clinical trial

Paul M. Peloso; R Andrew Moore; Wen-Jer Chen; Hsiao-Yi Lin; Davis Gates; Walter L. Straus; Zoran Popmihajlov

Abstract Background This analysis evaluated whether osteoarthritis patients achieving the greatest pain control and lowest pain states also have the greatest improvement in functioning and quality of life. Methods Patients (n = 419) who failed prior therapies and who were switched to etoricoxib 60 mg were categorized as pain responders or non-responders at 4 weeks based on responder definitions established by the Initiative on Methods, Measurement, and Pain (IMMPACT) criteria, including changes from baseline of ≥15%, ≥30%, ≥50%, ≥70% and a final pain status of ≤3/10 (no worse than mild pain). Pain was assessed at baseline and 4 weeks using 4 questions from the Brief Pain Inventory (BPI) (worst pain, least pain, average pain, and pain right now), and also using the Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain subscale. We examined the relationship between pain responses with changes from baseline in two functional measures (the BPI Pain Interference questions and the WOMAC Function Subscale) as well as changes from baseline in quality of life (assessed on the SF-36 Physical and Mental Component Summaries). We also sought to understand whether these relationships were influenced by the choice of the pain instrument used to assess response. We contrast the mean difference in improvements in the functional and quality of life instruments based on pain responder status (responder versus non-responder) and the associated 95% confidence limits around this difference. Results Patients with better pain responses were much more likely to have improved functional responses and improved quality of life, with higher mean changes in these outcomes versus pain nonresponders, regardless of the choice of IMMPACT pain response definition (e.g., using any of 15%, 30%, 50%, 70% change from baseline) or the final pain state of ≤3/10. There was an evident gradient, where higher levels of pain response were associated with greater mean improvements in function and quality of life. The finding that greater pain responses led to greater functional improvements and quality of life gains was not dependent on the manner in which pain was evaluated. Five different pain instruments (e.g., the 4 questions on pain from the BPI pain questionnaire and the WOMAC pain subscale) consistently demonstrated that pain responders had statistically significantly greater improvements in function and quality of life compared to pain non-responders. This suggests these results are likely to be generalizable to any validated pain measure for osteoarthritis. Conclusions Pain is an efficient outcome measure for predicting broader patient response in osteoarthritis. Patients who do not achieve timely, acceptable pain states over 4 weeks were less likely to experience functional or quality of life improvements. Implications Good pain improvements in osteoarthritis with a valid pain instrument are a proxy for good improvements in both function and quality of life. Therefore proper osteoarthritis pain assessment can lead to efficient evaluations in the clinic.


Expert Review of Vaccines | 2017

Studies with herpes zoster vaccines in immune compromised patients

Myron J. Levin; Eddy Bresnitz; Zoran Popmihajlov; Adriana Weinberg; Kai-Li Liaw; English Willis; Jeffrey R. Curtis

ABSTRACT Introduction: The active component of the herpes zoster vaccine (ZVL), licensed for people ≥50 years of age, is a live attenuated varicella-zoster virus. ZVL is contraindicated for immune compromised individuals, with limited regard to the degree of immunosuppression. Areas covered: This review evaluates phase I and II and observational studies for ZVL, and published reports of the off-label use of ZVL, for conditions and therapies for which investigators considered the risk-benefit for using ZVL to be favorable. It also discusses exploratory trials of ZVL for additional immune compromising conditions, and summarizes clinical guidelines from many countries and professional societies that are based upon recent investigations. Studies in immune compromised patients of investigational vaccines that do not contain live virus are reviewed. Expert commentary: It is likely that past and ongoing research with ZVL will define immune compromising diseases and/or therapies for which the risk-benefit for using ZVL vaccine is favorable. The main variables to consider in this assessment in immune compromised patients are safety, immunogenicity, protection against herpes zoster, and persistence of protection. Vaccination against herpes zoster prior to suppressing immunity is an important clinical strategy, although efficacy of this approach has not been evaluated in a clinical trial.


BMC Musculoskeletal Disorders | 2016

Evaluation of two doses of etoricoxib, a COX-2 selective non-steroidal anti-inflammatory drug (NSAID), in the treatment of Rheumatoid Arthritis in a double-blind, randomized controlled trial

Kara Bickham; Alan J. Kivitz; Anish Mehta; Nancy Frontera; Sandhya Shah; Paul Stryszak; Zoran Popmihajlov; Paul M. Peloso

BackgroundTreatment with non-steroidal anti-inflammatory drugs (NSAID) is a common component of treatment regimens for rheumatoid arthritis (RA). Etoricoxib is a COX-2 selective NSAID that has demonstrated efficacy in the treatment of RA at a dose of 90 mg. The current study further evaluated the efficacy of etoricoxib 60 mg and 90 mg in RA patients with active disease.MethodsThis was a 2-part, double-blind, placebo-controlled study in RA (NCT01208181). Patients were required to have a diagnosis of RA (according to ARA 1987 revised classification criteria) and were to demonstrate symptom flare upon discontinuation of previous NSAID treatment prior to randomization. Part I was a 6-week, placebo-controlled period to assess the efficacy of etoricoxib 90 mg and etoricoxib 60 mg, each compared to placebo, as well as to each other. Part II was a 6-week period to evaluate the potential benefit of dose escalation from etoricoxib 60 mg to etoricoxib 90 mg after 6 weeks exposure to etoricoxib 60 mg in Part I compared to maintaining a steady dose of etoricoxib 60 mg throughout Parts I and II. Primary endpoints were Disease Activity Score evaluating 28 joints and C reactive protein level (DAS28-CRP) index and Patient Global Assessment of Pain (Pain) score (0–100 mm VAS) after 6 weeks of treatment in Part I. Adverse events were monitored throughout the study.ResultsIn total, 1404 patients were randomized in a 2:7:7:8 ratio; 1228 patients completed Part I and 713 patients continued to Part II. Both etoricoxib doses were superior to placebo on both primary efficacy endpoints (p = 0.004 for 60 mg and p = 0.034 for 90 mg for DAS28-CRP; p < 0.001 for both doses for PGAP) in Part I. Further in Part I, etoricoxib 90 mg was not significantly different from 60 mg for DAS28-CRP, but did demonstrate a small, but statistically significant decrease in baseline PGAP score vs. 60 mg (p = 0.019). In Part II, there was no significant decrease in PGAP score after increasing to 90 mg in subjects with inadequate pain relief on 60 mg as compared to subjects who stayed on 60 mg. The incidence of AEs and SAEs were similar between etoricoxib 60 mg and 90 mg in both Part I and II.ConclusionBoth etoricoxib 90 mg and 60 mg are superior to placebo in relieving the symptoms of RA. Etoricoxib 90 mg vs 60 mg resulted in a statistically significant, though small, improvement in PGAP score, but not DAS28-CRP. Dose escalation from 60 mg to 90 mg in pain inadequate responders did not significantly improve efficacy. These results confirm the efficacy and tolerability of etoricoxib 90mg in patients with RA. In addition, this study demonstrated that etoricoxib 60 mg is also efficacious and well-tolerated in RA.Clinical Trial RegistrationNCT01208181 (registered September 22, 2010).


Vaccine | 2018

Immunogenicity and safety of zoster vaccine live administered with quadrivalent influenza virus vaccine

Myron J. Levin; Ulrike K. Buchwald; Julie L. Gardner; Jason Martin; Jon E. Stek; Elizabeth Brown; Zoran Popmihajlov

OBJECTIVES Randomized, blinded, placebo-controlled trial to evaluate the safety and immunogenicity of ZOSTAVAX™ (ZV) administered concomitantly with quadrivalent inactivated influenza vaccine (IIV4) in adults≥50years of age (NCT02519855). METHODS Overall, 440 participants were randomized into the Concomitant Group (CG) and 442 into the Sequential Group (SG). The CG received ZV and IIV4 at separate injection sites on Day 1 and matching placebo at Week 4. The SG received placebo and IIV4 (2015-2016 influenza season) at separate injection sites on Day 1 and ZV at Week 4. IMMUNOGENICITY ENDPOINTS Varicella-zoster virus (VZV) antibody geometric mean titer (GMT) and geometric mean fold-rise (GMFR) from baseline to 4weeks postvaccination, measured by glycoprotein enzyme-linked immunosorbent assay (gpELISA) and adjusted for age and prevaccination titer. Influenza strain-specific GMT at baseline and 4weeks postvaccination was measured by hemagglutination inhibition (HAI) assay. SAFETY ENDPOINTS Injection-site and systemic adverse experiences (AEs) within 28days following any vaccination and serious AEs throughout the study. RESULTS The adjusted VZV antibody GMT ratio (CG/SG) was 0.87 (95%CI: 0.80, 0.95), meeting the prespecified noninferiority criterion. The VZV antibody GMFR in the CG was 1.9 (95%CI: 1.76, 2.05), meeting the acceptability criterion. Influenza antibody GMT ratios for A/H1N1, A/H3N2, B/Yamagata and B/Victoria were 1.02 (95%CI: 0.88, 1.18), 1.10 (95%CI: 0.94, 1.29), 1.00 (95%CI: 0.88, 1.14), and 0.99 (95%CI: 0.87, 1.13), respectively. The frequency of vaccine-related injection-site and systemic AEs was comparable between groups. No vaccine-related serious AE was observed. CONCLUSION The concomitant administration of ZV and IIV4 to adults≥50years of age induced VZV-specific and influenza-specific antibody responses that were comparable to those following administration of either vaccine alone, and was generally well tolerated.


The Journal of Infectious Diseases | 2018

Persistence of Varicella-Zoster Virus Cell-Mediated Immunity After the Administration of a Second Dose of Live Herpes Zoster Vaccine

Adriana Weinberg; Zoran Popmihajlov; Kenneth E. Schmader; Michael Johnson; Yupanqui Caldas; Adriana Tovar Salazar; Jennifer Canniff; Barbara J. McCarson; Jason Martin; Lei Pang; Myron J. Levin

Protection against zoster conferred by zoster vaccine live (ZVL; Zostavax) wanes over time. We compared varicella-zoster virus cell-mediated immunity (VZV-CMI) of adults ≥70 years who received a second dose of ZVL ≥10 years after the initial dose with de novo-immunized age-matched controls. Before and during the first year after vaccination, VZV-CMI was significantly higher in reimmunized compared with de novo vaccinees. At 3 years, VZV-CMI differences between groups decreased and only memory responses remained marginally higher in reimmunized participants. In conclusion, the increase in VZV-CMI generated by reimmunization with ZVL is at least equally persistent compared with de novo immunization.


Human Vaccines & Immunotherapeutics | 2018

A post hoc analysis utilizing the FDA toxicity grading scale to assess injection site adverse events following immunization with the live attenuated Zoster Vaccine (ZVL)

Zoran Popmihajlov; Lei Pang; Elizabeth Brown; Amita Joshi; Shu-Chih Su; Susan S. Kaplan; English Willis

ABSTRACT Background: ZOSTAVAX (ZVL; Zoster Virus Live), is a single dose, live, attenuated vaccine licensed for the prevention of herpes zoster (HZ) and post herpetic neuralgia (PHN) in adults ≥50 years of age. Injection site adverse events (AEs) of erythema, swelling and pain were solicited within 5 days post vaccination in the 2 pivotal studies of ZVL; ZEST (ZOSTAVAX Efficacy and Safety Trial) and SPS (Shingles Prevention Study). Protocol specified criteria were used to report the frequency and intensity of injection site AEs in ZEST and SPS studies. Subsequently, the FDA Toxicity Grading Scale provided guidance for uniform assessment of AEs across all adult vaccine clinical trials. The objective of this post-hoc analysis was to categorize the previously reported injection site AEs in two pivotal trials of ZVL according to the current FDA Toxicity Grading Scale. Methods: The current FDA Toxicity Grading Scale provides a measure for classifying injection site AEs by four grades [Grade 1 (mild); Grade 2 (moderate); Grade 3 (severe) and Grade 4 (life threatening)]. Injection site erythema, swelling, and pain intensity gradings were assigned to the respective FDA Toxicity Grade based on this appropriation. A descriptive analysis of the proportion and risk difference (within 95% confidence intervals) of injection site AEs per the FDA Toxicity Grading Scale is provided. Results: The frequency of injection site AEs (erythema, swelling, pain) after subcutaneous vaccination with ZVL were higher in recipients of ZVL compared with placebo. Majority of the injection site AEs observed were Grade 1 (mild) or Grade 2 (moderate) in intensity. Additionally, Grade 3 (severe) injection site AEs were observed infrequently. Conclusions: Application of the FDA Toxicity Grading Scale provides a uniform AE assessment tool across different adult vaccines. This post hoc summary of injection site AEs using FDA Toxicity Grading Scale provides further evidence of low frequency of severe injection site AEs post ZVL vaccination.


Clinical Infectious Diseases | 2018

Safety and Immunogenicity of Zoster Vaccine Live in Human Immunodeficiency Virus–Infected Adults With CD4+ Cell Counts >200 Cells/mL Virologically Suppressed on Antiretroviral Therapy

Constance A. Benson; Janet Andersen; Bernard Macatangay; Robbie B. Mailliard; Charles R. Rinaldo; Sarah W. Read; Dawn R Bozzolo; Lynette Purdue; Cheryl Jennings; Michael C. Keefer; Marshall J. Glesby; Pablo Tebas; Amy Falk Russell; Jason Martin; Paula W. Annunziato; Zoran Popmihajlov; Jeffrey L. Lennox

Background Herpes zoster (HZ) risk is increased in human immunodeficiency virus (HIV)-infected persons. Live attenuated zoster vaccine (ZV) reduces HZ incidence and severity in adults; safety and immunogenicity data in HIV-infected adults are limited. Methods We conducted a randomized, double-blind, placebo-controlled trial in HIV-infected adults virally suppressed on antiretroviral therapy (ART). Participants, stratified by CD4+ count (200-349 or ≥350 cells/µL), were randomized 3:1 to receive ZV or placebo on day 0 and week 6. The primary endpoint was serious adverse event or grade 3/4 signs/symptoms within 6 weeks after each dose. Immunogenicity (varicella zoster virus [VZV]-specific glycoprotein enzyme-linked immunosorbent assay and interferon-γ enzyme-linked immunospot assay responses) was assessed at 6 and 12 weeks postvaccination. Results Of 395 participants (296 ZV vs 99 placebo), 84% were male, 47% white, 29% black, and 22% Hispanic; median age was 49 years. Safety endpoints occurred in 15 ZV and 2 placebo recipients (5.1% [95% confidence interval {CI}, 2.9%-8.2%] vs 2.1% [95% CI, .3%-7.3%]; P = .26). Injection site reactions occurred in 42% of ZV (95% CI, 36.3%-47.9%) vs 12.4% of placebo recipients (95% CI, 6.6%-20.6%) (P < .001). Week 12 median natural log VZV antibody titer was higher for ZV (6.30 [Q1, Q3, 5.64, 6.96]) vs placebo (5.48 [Q1, Q3, 4.63, 6.44]; P < .001) overall and in the high CD4+ stratum (P = .003). VZV antibody titers were similar after 1 or 2 ZV doses. Polymerase chain reaction-confirmed HZ occurred in 2 participants (1 ZV; 1 placebo); none was vaccine strain related. Conclusions Two doses of ZV in HIV-infected adults suppressed on ART with CD4+ counts ≥200 cells/µL were safe and immunogenic. Clinical Trials Registration NCT00851786.

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Myron J. Levin

University of Colorado Denver

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Adriana Weinberg

University of Colorado Denver

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Michael Johnson

University of Colorado Denver

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Yupanqui Caldas

University of Colorado Denver

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Alice Cho

University of Colorado Denver

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