Neal Bhatia, M.D. Therapeutics Clinical Research, San Diego, CA INTRODUCTION • Imiquimod is an immune response modifier that is FDA approved for the treatment of actinic keratosis (AKs), external genital warts, and superficial basal cell carcinoma.1 • Imiquimod is a potent inducer of interferon (IFN)-α and other pro-in- flammatory cytokines.2 • Some patients treated with topical imiquimod develop influenza-like symptoms (e.g., myalgia, malaise, headache, low-grade fever, and fatigue) that may be related to elevated levels of pro-inflammatory cytokines associated with application of the drug.3 • This study was carried out to assess correlations between influen- za-like symptoms and cytokine levels in patients who applied imiqui- mod cream to their skin for 14 days. Other variables that might influ- ence emergence and severity of symptoms, including age, severity of local skin reactions, the amount of surface area involved, and the area of the body exposed were also evaluated. METHODS Design • Single-center open-label study. Subjects • 22 men and women with 5-20 AKs between 30 and 89 years of age. Treatment • The designated treatment area (entire face or balding scalp; or chest or upper extremities) was cleansed with an approved cleanser and allowed to dry for 5 minutes prior to application of imiquimod 3.75% cream to a total are of 200 cm2. The treatment period was 14 days. Endpoints • Clearance of AKs. • Frequency of symptoms indicative of an influenza-like response, in- cluding, fever, headache, fatigue, malaise, gastrointestinal symptoms, dizziness, myalgia, and arthralgia. • Change from baseline at subsequent study visits (days 8, 15, 43, and 57 [end of study]) in: • Cytokines – interleukin (IL) -6, IL-8, IL-12, IL-13, IL-2 receptor (R), tumor necrosis factor-α (TNF), IFN-α, and IFN-γ • Frequency of local skin reactions of erythema, scabbing/crusting, edema, erosion/ulceration, exudate, flaking/scaling/dryness and pruritus. RESULTS Subjects • Characteristics of subjects enrolled and areas treated are summa- rized in Table 1. Clearance of AKs • All but one subject experienced either complete clearance or partial clearance of actinic keratoses with no more than 3 remaining in the treatment field. Table 1. Subject characteristics Characteristic N=22 Age (years) Mean (standard deviation) 62.8 (8.99) Median 59 Age group, n (%) ≥30 years to ≤59 years 12 (54.5) ≥60 years to ≤ 89 years 10 (45.5) Sex, n (%) Female 7 (31.8) Male 15 (68.2) Area of Treatment n (%) Entire Face or Balding Scalp 11 (50.0%) Chest or Upper Extremities 11 (50.0%) Frequency of Influenza-like Symptoms • Systemic symptoms characteristic of influenza occurred infrequently during the treatment period (Table 2). Table 2. Influenza-like symptoms that emerged during treatment Symptom Occurrence During Treatment (n) Fever 1 Myalgia 1 Fatigue 0 Malaise 1 Headache 4 Gastrointestinal symptoms 3 Dizziness 3 Arthralgia 3 Relationship Between Clearance of AKs and Influenza-like Symptoms • There was no apparent relationship between clearance on the occur- rence of symptoms (Table 3). Table 3. AK clearance in subjects with and without influenza-like symptoms Systemic Symptoms during treatment Baseline AK count, mean (median) End of treatment AK count, mean (median) Yes 14.0 (14.0) 2.9 (0.0) No 13.7 (14.0) 2.4 (1.0) Changes from Baseline in Cytokine Levels • Twelve subjects had elevations in at least one cytokine at one or more post-baseline visits (Table 4). • There were no apparent relationships between the occurrences of cytokine elevations and either the occurrence of influenza-like symp- toms or local skin reactions (Figure 1). Table 4. Cytokine elevations during treatment. Subject Visit 1 Visit 2 Visit 3 Visit 4 4 IL-2 IL-2 IL-2, IL-13 IL-2, IL-2R, IL-13 7 IL-13 IL-13 8 IFN-γ IFN-γ IFN-γ IFN-γ 10 IL-2, IL-12 IL-2 IL-2, IL-12, IFN-γ 11 IL-6, IL-2R, IL-13 IL-6, IL-2R, IL-13 IL-6, IL-2R, IL-13 12 IL-13 13 IL-13 IL-13 15 IL-8, IL-13 18 IL-13 20 IL-13 IL-13 21 IL-13 IL-12 23 IL-8 IL-13 IL-13 Figure 1. Temporal relationships among systemic symptoms (SS), local skin reactions (LSR) and elevations in cytokines (EL CYT) for patients with and without SS. No Systemic Symptoms Systemic Symptoms V1 V2 V3 V4 V5 V1 V2 V3 V4 V5 SS LSR EL CYT SS LSR EL CYT SS LSR EL CYT SS LSR EL CYT SS LSR EL CYT SS LSR EL CYT SS LSR EL CYT SS LSR EL CYT SS LSR EL CYT SS LSR EL CYT SS LSR EL CYT SS LSR EL CYT SS LSR EL CYT CONCLUSION • Treatment on the face led to more incidence of flu like symptoms in younger patients • Elevations in pro-inflammatory cytokines did not appear to predict the development of either sys- temic symptoms or local skin reactions. • Elderly patients treated on the body were less likely to develop reactions of the four groups. REFERENCES 1. Imiquimod Cream. 2010. https://www.accessdata.fda.gov/drugsatfda_docs/ label/2010/020723s022lbl.pdf. 2. Nerurkar L, et al. Sci Rep. 2017;7:16570. 3. Cantisani C, et al. Recent Pat Inflamm Allergy Drug Discov. 2012;6:65-69. ACKNOWLEDGMENTS The author would like to recognize the contributions of AraMed Strategies Inc for scientific analysis and editorial support. Study funding was graciously provided by Ortho Dermatologics. • Empty boxes (gray): subject • Yellow boxes: subject had no symptoms with a score of 2 or more. • Pink boxes: Subject had at most one symptom scored a 2 (moderate) and no symp- toms scored above 2. • Red boxes: Subject had more than one symptom scored at two or more or at least one symptom scored as a 3 (severe). MEASURING THE PREDICTIVE VALUE OF SEROLOGICAL QUANTIFICATION OF CYTOKINES WITH THE ONSET OF INFLUENZA-LIKE SIGNS AND SYMPTOMS INDUCED BY IMIQUIMOD 3.75% CREAM: RESULTS OF A SINGLE CENTER, OPEN-LABEL, PROOF OF CONCEPT TRIAL