John Koo

University of California, San Francisco, San Francisco, California, United States

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Publications (109)294.63 Total impact

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    ABSTRACT: Background: Tumor necrosis factor-α inhibitors (TNFi) are the most widely used systemic treatments for patients with psoriasis and psoriatic arthritis. There currently exists a U.S. Food and Drug Administration issued warning label on all TNFi for "rare cases of new onset or exacerbation of central nervous system demyelinating disorders." The aim of this review was to update the incidence of TNFi-induced demyelinating diseases. Methods: Pubmed database was searched for safety data regarding demyelinating disease secondary to TNFi therapy prescribed for psoriasis. Results: In clinical trials: 6990 patients had received treatment with etanercept with one reported case of multiple sclerosis; 5204 patients were treated with adalimumab with no cases identified and 2322 patients were treated with infliximab with one case of demyelinating polyneuropathy. Outside of clinical trials: 19 individual cases of demyelinating disorders from TNFi treatment have been reported. Conclusion: Although there is potential for TNF blockade to lead to demyelination of the central and peripheral nervous systems, the results of the present review suggest that demyelinating diseases associated with TNFi are extremely rare. TNFi are not recommended for use in patients with a personal history of demyelinating disease. However, with clinical vigilance and individualized treatment regimen, TNFi may be safe for use in other patients.
    No preview · Article · Feb 2016 · Journal of Dermatological Treatment

  • No preview · Conference Paper · Dec 2015
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    ABSTRACT: Background: An aerosol foam formulation of fixed combination calcipotriene 0.005% (as hydrate; Cal) plus betamethasone dipropionate 0.064% (BD) was developed to improve psoriasis treatment. Objectives: To compare the efficacy and safety of Cal/BD aerosol foam with Cal/BD ointment after 4 weeks. Methods: In this Phase II, multicenter, investigator-blind, 4-week trial, adult patients with psoriasis vulgaris were randomized to Cal/BD aerosol foam, Cal/BD ointment, aerosol foam vehicle or ointment vehicle (3:3:1:1). The primary efficacy endpoint was the proportion of patients at week 4 who achieved treatment success (clear or almost clear with at least a two-step improvement) according to the physician's global assessment of disease severity. Results: In total, 376 patients were randomized. At week 4, significantly more patients using Cal/BD aerosol foam achieved treatment success (54.6% versus 43.0% [ointment]; p = 0.025); mean modified (excluding the head, which was not treated) psoriasis area and severity index score was significantly different between Cal/BD aerosol foam and Cal/BD ointment (mean difference -0.6; p = 0.005). Rapid, continuous itch relief occurred with both active treatments. One adverse drug reaction was reported with Cal/BD aerosol foam (application site itch). Conclusions: Cal/BD aerosol foam demonstrates significantly greater efficacy and similar tolerability compared with Cal/BD ointment for psoriasis treatment.
    Preview · Article · Oct 2015 · Journal of Dermatological Treatment
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    ABSTRACT: Background: Early clinical studies suggested that the anti-interleukin-17 receptor A monoclonal antibody brodalumab has efficacy in the treatment of psoriasis. Methods: In two phase 3 studies (AMAGINE-2 and AMAGINE-3), patients with moderate-to-severe psoriasis were randomly assigned to receive brodalumab (210 mg or 140 mg every 2 weeks), ustekinumab (45 mg for patients with a body weight ≤100 kg and 90 mg for patients >100 kg), or placebo. At week 12, patients receiving brodalumab were randomly assigned again to receive a brodalumab maintenance dose of 210 mg every 2 weeks or 140 mg every 2 weeks, every 4 weeks, or every 8 weeks; patients receiving ustekinumab continued to receive ustekinumab every 12 weeks, and patients receiving placebo received 210 mg of brodalumab every 2 weeks. The primary aims were to evaluate the superiority of brodalumab over placebo at week 12 with respect to at least a 75% reduction in the psoriasis area-and-severity index score (PASI 75) and a static physician's global assessment (sPGA) score of 0 or 1 (clear or almost clear skin), as well as the superiority of brodalumab over ustekinumab at week 12 with respect to a 100% reduction in PASI score (PASI 100). Results: At week 12, the PASI 75 response rates were higher with brodalumab at the 210-mg and 140-mg doses than with placebo (86% and 67%, respectively, vs. 8% [AMAGINE-2] and 85% and 69%, respectively, vs. 6% [AMAGINE-3]; P<0.001); the rates of sPGA scores of 0 or 1 were also higher with brodalumab (P<0.001). The week 12 PASI 100 response rates were significantly higher with 210 mg of brodalumab than with ustekinumab (44% vs. 22% [AMAGINE-2] and 37% vs. 19% [AMAGINE-3], P<0.001). The PASI 100 response rates with 140 mg of brodalumab were 26% in AMAGINE-2 (P=0.08 for the comparison with ustekinumab) and 27% in AMAGINE-3 (P=0.007). Rates of neutropenia were higher with brodalumab and with ustekinumab than with placebo. Mild or moderate candida infections were more frequent with brodalumab than with ustekinumab or placebo. Through week 52, the rates of serious infectious episodes were 1.0 (AMAGINE-2) and 1.3 (AMAGINE-3) per 100 patient-years of exposure to brodalumab. Conclusions: Brodalumab treatment resulted in significant clinical improvements in patients with moderate-to-severe psoriasis. (Funded by Amgen; AMAGINE-2 and AMAGINE-3 numbers, NCT01708603 and NCT01708629.).
    No preview · Article · Oct 2015 · New England Journal of Medicine
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    ABSTRACT: A common therapeutic modality for psoriasis includes the combination of phototherapy with topical treatments. The recent development of targeted phototherapy with the excimer laser and spray formulations for topical treatments has increased the efficacy and convenience of these combinational therapies. Herein, we aim to assess the efficacy of a novel combination of therapies using the 308-nm excimer laser, clobetasol propionate spray and calcitriol ointment for the treatment of moderate to severe generalized psoriasis. In this 12-week study, patients with moderate to severe psoriasis received twice weekly treatments with a 308-nm excimer laser combined with clobetasol proprionate twice daily for a month followed by calcitriol ointment twice daily for the next month. Of the 30 patients enrolled, 83% of patients (25/30) achieved PASI-75 (65%-94%, 95% confidence interval) at week 12. For PGA, there was an estimated decrease of 3.6 points (3.1 to 4.1, 95% CI, p<0.0005) by week 12. In conclusion, the combination of excimer laser with alternating clobetasol and calcitriol application has shown to be a promising combination of therapies for treatment of moderate to severe generalized psoriasis. Further evaluation may be conducted with a larger study inclusive of control groups and head-to-head comparisons against topical steroid and UVB therapy as monotherapies.
    No preview · Article · Sep 2015 · Journal of Dermatological Treatment
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    ABSTRACT: Background: Difficulty in patient access to care and affordability are major problems faced by our dermatology specialty in the United States. However, Taiwan provides adequate and affordable dermatologic care for all of its citizens. Herein we describe our first-hand observations and findings of the outpatient dermatology experience in Taipei, and contrast it to the experience in the United States. Observation: In Taipei, Taiwan, we observed patient management, electronic documentation, and billing during outpatient dermatology visits in five settings: one academic hospital outpatient dermatology department, one academic hospital Information Technology department, and three private dermatologists' offices. Through our observations, we found that the dermatology specialty in Taiwan is able to overcome challenges with access to care and affordability through three key system features: (1) short yet frequent patient visits (2) close proximity of ancillary staff, and (3) an integrated and paperless electronic medical record and billing system. Conclusions: The Taiwan system is attained with some sacrifice, such as shorter time spent with patients and less personalized care. However, because this system can meet the basic dermatological needs of the entire population, possibly better than our current system, it behooves us to study the Taiwan system with respect and care.
    No preview · Article · Aug 2015 · Dermatology online journal
  • Rachel McAndrew · Ethan Levin · John Koo
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    ABSTRACT: Increased knowledge of the molecular regulatory mechanisms that contribute to the pathogenesis of psoriasis and other inflammatory diseases has created new opportunities for the development of targeted drug therapy for inflammatory conditions. Two new oral medications, apremilast and tofacitinib, have been developed for their immunomodulatory properties, and their potential efficacy in treating psoriasis is being evaluated. We reviewed phase III randomized, placebo-controlled clinical trial results for apremilast and tofacitinib for efficacy and safety in psoriasis. Psoriasis Area and Severity Index (PASI) 75 after 16 weeks for apremilast was between 28.8% and 33.1%. PASI 75 was 39.5% after 12 weeks on tofacitinib 5 mg, and 63.6% after 12 weeks on tofacitinib 10 mg. Common side effects for both drugs included nasopharyngitis and upper respiratory tract infections. Gastrointestinal disturbance was common for apremilast. Dyslipidemia and infections were more common with tofacitinib than placebo. Both new oral medications, apremilast and tofacitinib, appear to be effective in treating psoriasis. J Drugs Dermatol. 2015;14(8):786-792.
    No preview · Article · Aug 2015 · Journal of drugs in dermatology: JDD
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    ABSTRACT: Psoriasis is a chronic immune-mediated inflammatory condition that affects 2-3% of the population. Apremilast was FDA-approved in March 2014 for the treatment of psoriatic arthritis and in September 2014 for the treatment of moderate to severe plaque psoriasis. Apremilast appears to have lower efficacy than some biologic agents such as adalimumab and ustekinumab, which achieve a PASI-75 in approximately 70% of patients after 12-16 weeks of therapy. However, its ease of administration as an oral agent coupled with a mild side effect profile make it an attractive option for psoriasis treatment. Herein, we present a patient with a 17-year history of plaque type psoriasis recalcitrant to topical, oral, and biologic mediations who attained near-complete remission after therapy with a combination of adalimumab and apremilast.
    No preview · Article · Jul 2015 · Dermatology online journal
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    ABSTRACT: Phototherapy is an effective treatment for several inflammatory skin conditions. While its utility is well-recognized (e.g. 45% of American Academy of Dermatology members prefer phototherapy as a first-line psoriasis treatment) [1] its use has significantly declined in the U.S. [2, 3] Part of the problem may be the training of residents. A survey conducted in 1994, which included 66 dermatology chief residents, found that over 50% of respondents received fewer than 3 hours of phototherapy training annually, and 55% reported no hands-on tutorials. [4] Many residents felt ill-prepared to provide phototherapy. Based on a similar study surveying dermatology residents, our results indicate that 20 years later, phototherapy training remains lacking. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    No preview · Article · May 2015 · Photodermatology Photoimmunology and Photomedicine
  • Eric Sorenson · John Koo
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    ABSTRACT: Biologic agents have greatly enhanced the treatment of moderate-to-severe plaque psoriasis. Previous reviews of the safety of biologic agents have included patients with conditions other than psoriasis and/or have not used statistical significance as the primary analytic focus. Our aim was to review the current literature to identify significantly increased adverse events associated with the use of etanercept, adlimumab and ustekinumab for the treatment of moderate-to-severe plaque psoriasis. We performed a search of Ovid MEDLINE and the Cochrane Library to identify clinical trials, open-label extension studies and meta-analyses reporting statistical analysis of adverse events associated with the use of etanercept, adlimumab and ustekinumab for the treatment of moderate-to-severe plaque psoriasis. We identified 17 clinical trials, 2 open-label extension studies and 8 meta-analyses. Adverse events reported to be significantly increased included squamous cell carcinoma (SCC), injection-site reaction, and headache associated with etanercept, overall nonmelanoma skin cancer (NMSC), SCC, and upper respiratory tract infection associated with adalimumab, and no significantly increased adverse events associated with ustekinumab. Current evidence suggests that when analyzed among patients with plaque psoriasis, few adverse effects of the biologic agents etanercept, adalimumab and ustekinumab have reached statistical significance. Further long-term studies conducting analysis of statistical significance should be performed.
    No preview · Article · Apr 2015 · Journal of Dermatological Treatment
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    ABSTRACT: Psoriasis is a chronic immune disorder that affects 2-3% of the US population. Ustekinumab, a monoclonal antibody against IL-23/12, has shown great efficacy in treating psoriasis. Here we present a rare finding of a patient with plaque-type psoriasis who was diagnosed with congestive heart failure after initiating treatment with ustekinumab. The patient experienced full recovery of cardiac function upon discontinuation of ustekinumab.
    Preview · Article · Apr 2015
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    ABSTRACT: Chronic graft-vs-host disease (GVHD) affects 50% to 70% of patients who receive allogeneic hematopoietic cell transplants (HCTs), and the skin is the most common site of involvement. Chronic cutaneous GVHD can present with sclerotic or nonsclerotic changes of the skin and often requires treatment with systemic immunosuppressants, extracorporeal photopheresis, or phototherapy. We describe the first reported case, to our knowledge, of the effective treatment of sclerotic chronic cutaneous GVHD with narrowband UV-B (NB UV-B) phototherapy. A woman in her 40s presented with sclerotic chronic GVHD of the skin 6 years after HCT for treatment of chronic myelogenous leukemia. The patient's cutaneous disease progressed despite treatment with prednisone and oral tacrolimus. The patient was initiated on NB UV-B phototherapy 3 times per week, resulting in clinically significant improvement of cutaneous lesions over the first 2 months. The NB UV-B regimen allowed for a reduction of prednisone dose and continued control of cutaneous GVHD over 6 months of therapy. Our case report describes the successful use of NB UV-B phototherapy for the treatment of sclerotic chronic cutaneous GVHD. Further study should be performed to evaluate the effectiveness of this therapeutic modality for patients with sclerotic chronic cutaneous GVHD.
    No preview · Article · Mar 2015 · JAMA Dermatology
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    ABSTRACT: Effective treatments for moderate to severe psoriasis are phototherapy and biologics. These treatments are similar in that they both decrease cutaneous immune system hyperactivity yet do so via different mechanisms. Our patient, a 63 year old Asian male had a rapid response to treatment with the high dose excimer laser, having previously failed treatment with 28 weeks of ustekinumab therapy. A pre-treatment biopsy of a psoriatic plaque was found to contain relatively low levels of IFN-γ (Th1) and IL-17 (Th17) secreting T cells. Following treatment with the excimer laser, the patient had a quick improvement in PASI that was reflected by a 3-fold reduction in the number of live T cells found in the post-treatment biopsy. Although ustekinumab and the excimer laser both result in decreased levels of these cytokines, the excimer laser directly causes apoptosis of T cells and induces DNA damage in antigen presenting cells. Thus, the broader effects of phototherapy on immune cells compared to the targeted inhibition of IL-12 and IL-23 by ustekinumab likely account for the superior response observed.
    No preview · Article · Mar 2015 · Dermatology online journal
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    Full-text · Article · Jan 2015 · Journal of the American Academy of Dermatology
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    ABSTRACT: Patient satisfaction is an important component of dermatological care that reflects patients' perspectives on the care they receive. While physicians' expertise and judgment should always remain the foundation of providing appropriate and effective care, the patient experience can also be influenced by interpersonal relationships, expectations, and a sense of agency in the treatment patients receive. Dermatology providers can use practical techniques such as sitting rather than standing, reframing the concept of cure, and engaging patients in treatment decisions to improve the patient-provider experience and thereby optimize patient satisfaction.
    No preview · Article · Jan 2015 · American Journal of Clinical Dermatology

  • No preview · Article · Jan 2015 · Journal of the Dermatology Nurses' Association
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    ABSTRACT: Patient satisfaction has been and is of growing importance in healthcare. Recent healthcare initiatives aim to provide physicians with performance feedback reports based partially on patient completed surveys; thus, patient satisfaction will be an even more important determinant of high quality care. In the field of dermatology, patient satisfaction is particularly relevant and at times difficult to achieve, since many patients are plagued with chronic skin diseases often requiring intensive topical regimens or undesirable systemic immunosuppressants. The discussion of patient satisfaction is usually restricted to encounters with the general clinic population leaving encounters with difficult patients largely underreported; therefore, we provide examples of more common difficult patient encounters a dermatologist may face with specific recommendations on how to best optimize patient satisfaction.
    No preview · Article · Sep 2014 · Clinics in Dermatology
  • Steven R Feldman · Mona Malakouti · John Ym Koo
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    ABSTRACT: The raised, scaly, and erythematous plaques associated with psoriasis can be cosmetically disfiguring, which may provoke disgust, fear, and aversion in others. Consequently, the social stigma of psoriasis can be devastating for patients, evoking feelings of shame and anxiety about how they are perceived. In recent years, appreciation of psoriasis as a disease that can cause social distress and impairment has increased. This review discusses the manifold social burdens of psoriasis; different and emerging therapies that may mitigate these burdens by improving outcomes associated with the underlying disease; and psoriasis management in the context of healthcare reform changes focused on assessing the quality and value of patient care. The social impact of psoriasis is substantial (eg, affecting interpersonal relationships, sexual function, intimacy, occupational success). Undertreatment of psoriasis continues, despite evidence that biologic agents may lessen the physical and social burdens and provide greater patient satisfaction than conventional therapy. Changes in healthcare place an even greater emphasis on measurable outcomes, including patient satisfaction. Increased understanding of the social burden of psoriasis may lead to provision of more comprehensive, holistic care that is in concordance with the evolving restructured reimbursement system.
    No preview · Article · Aug 2014 · Dermatology online journal
  • Eva Wang · John Koo · Elie Levy

    No preview · Article · Aug 2014 · Journal of the American Academy of Dermatology
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    ABSTRACT: Phototherapy is often used to treat inflammatory skin conditions such as psoriasis and eczema. Much progress has recently been made in understanding the mechanisms underlying the local, cutaneous immune effects induced by phototherapy. Unlike many immunosuppressive drugs used in the management of inflammatory skin disease, phototherapy not only targets effector immune cells but also appears to up-regulate regulatory T cells (Tregs). Additionally, phototherapy reverses epidermal barrier abnormalities common in these diseases, allowing for restoration of cutaneous homeostasis. J Drugs Dermatol. 2014;13(5):564-568.
    No preview · Article · May 2014 · Journal of drugs in dermatology: JDD

Publication Stats

2k Citations
294.63 Total Impact Points


  • 1997-2015
    • University of California, San Francisco
      • Department of Dermatology
      San Francisco, California, United States
  • 2013
    • University of Texas at San Antonio
      San Antonio, Texas, United States
  • 2006-2013
    • University of Southern California
      • Keck School of Medicine
      Los Angeles, California, United States
  • 2012
    • University of San Francisco
      San Francisco, California, United States
    • Kaiser Permanente
      Oakland, California, United States
  • 2010
    • University of Pittsburgh
      • Department of Dermatology
      Pittsburgh, Pennsylvania, United States
  • 2007
    • University of California, Irvine
      • Department of Pediatrics
      Irvine, California, United States
  • 2005
    • California State University, Sacramento
      Sacramento, California, United States
  • 1999
    • Icahn School of Medicine at Mount Sinai
      • Department of Dermatology
      Borough of Manhattan, New York, United States