Background Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system caused by reactivation of the polyomavirus John Cunningham (JCV) in the setting of immunosuppression. It has been described in patients with hematologic malignancies including multiple myeloma (MM), solid organ malignancies, granulomatous and inflammatory diseases, transplant recipients, lymphopenic patients (including patients with HIV) and with the use of certain drugs (rituximab, natalizumab). We present the first report to our knowledge of a patient with MM developing PML in association with daratumumab and pomalidomide therapy. Case Report A 63yo woman with relapsed/refractory IgA-Lambda MM on daratumumab and pomalidomide, presented to the emergency department after noticing difficulty putting her hair up in a ponytail. Her MM was diagnosed in 2003 and treated with steroids, high-dose melphalan and autologous stem cell transplant, maintenance therapy with thalidomide, switched to lenalidomide; upon relapse in 2010, she was treated with bortezomib, doxorubicin and dexamethasone, followed by bortezomib maintenance. Ten months prior to presentation, she relapsed and was started on daratumumab and pomalidomide, achieving an unconfirmed complete response (uCR), complicated by acquired hypogammaglobulinemia for the prior 8 months without infections. She developed progressive left arm weakness and gait instability; she denied any fevers, dysarthria, vision changes, headaches or seizures. On exam, she was alert and oriented; no cranial nerve abnormality; calculation, concentration and recall were intact; 4/5 strength in left upper extremity and 5/5 strength in all other extremities with preserved sensation and reflexes; coordination intact but a hemiparetic gait; rest of the exam was unremarkable. A brain MRI showed patchy and confluent areas of T2 hyperintense signal in the right greater than left cerebral hemispheres. She underwent a lumbar puncture which was positive for JCV by PCR (98 copies/mL) in her CSF and negative for neoplastic involvement by flow cytometry. The rest of her work-up was unremarkable. A diagnosis of PML was made and daratumumab and pomalidomide were discontinued. On follow-up brain MRIs four and eight weeks later, she had persistent extensive asymmetric patchy T2 hyperintense signal. Repeat LP revealed stable JCV in the CSF (95 copies/mL). Despite the lack of radiologic improvement, she had a remarkable clinical response with near resolution of neurologic symptoms and remains in an uCR. Discussion PML has been reported in association with multiple drugs used in the management of MM including corticosteroids, alkylating agents (cyclophosphamide, melphalan), immunomodulatory drugs (thalidomide, lenalidomide) and proteasome inhibitors (bortezomib, ixazomib), however, an association with pomalidomide or daratumumab has not yet been reported. In a clinical trial of daratumumab and pomalidomide for MM, a case of PML was reported, however, it was not considered to be related to these agents given that the patient received only one dose of daratumumab (Chari A. Blood 2017). PML has been reported in patients with primary hypogammaglobulinemia, however, it is not known whether acquired hypogammaglobulinemia - either due to MM or its therapy - is a risk factor for PML. Furthermore, the role for IVIG in the primary prevention or treatment of PML has not been clearly defined and warrants further study. The current treatment approach of PML remains the restoration of the host's adaptive immune response, including the discontinuation of immunosuppressive agents, unfortunately, evidence is lacking for any specific pharmacologic treatment. Recently, immune checkpoint inhibitors have shown clinical improvement or stabilization in small cohorts of patients with PML (NEJM 2019;380), however, given the safety concerns regarding their use in MM (KEYNOTE-183,-185) and the rapid clinical response seen in this case, no further therapy was instituted. This is the first report of pomalidomide and daratumumab as potential drugs associated with PML. Although it is not possible to ascertain their direct role in the reactivation of JCV, it should help clinicians recognize this potentially fatal complication in patients receiving either immunomodulatory drugs or anti-CD38 monoclonal antibodies, since prompt discontinuation may be life-saving. Disclosures Perry: Celgene: Speakers Bureau. Coleman:Gilead, Bayer, Celgene: Consultancy, Research Funding, Speakers Bureau; Kite Pharmaceuticals: Equity Ownership; Merck: Research Funding; Pharmacyclics: Speakers Bureau. Rossi:Janssen, Celgene, Amgen: Consultancy; BMS: Research Funding. Niesvizky:Takeda, Amgen, BMS, Janssen, Celgene: Consultancy, Research Funding.

Acute promyelocytic leukemia has good prognosis in view of the high complete remission and survival rates achieved with therapies containing all-trans retinoic acid or arsenic trioxide. However, there is a significant risk of death during induction due to hemorrhage secondary to disseminated intravascular coagulation. This has contributed to a gap in the prognosis of patients between developed and developing countries. The International Consortium on Acute Promyelocytic Leukemia was created in 2005 and proposed a treatment protocol based on daunorubicin and all-trans retinoic acid stratified by risk geared toward developing countries. Herein are presented the results from the first patient cohort treated in a single developing country hospital employing a slightly modified version of the International Consortium protocol in a real life setting. Twenty patients with acute promyelocytic leukemia were enrolled: 27.8% had low-risk, 55.6% intermediate risk and 16.7% high-risk. The complete remission rate was 94.4% after a median of 42 days. Both relapse rates and death rates were one patient (5.5%) each. No deaths were observed during consolidation. After a median follow-up of 29 months, the overall survival rate was 89.1%. Efficacy and safety of the International Consortium on Acute Promyelocytic Leukemia protocol has been reproduced in acute promyelocytic leukemia patients from a developing country.

Background: Renal impairment is a frequent complication of multiple myeloma (MM) associated with poor prognosis and decreased overall survival; and can complicate drug dosing, limit treatment options and lead to a higher incidence of adverse events. Daratumumab is an anti-CD38 monoclonal antibody indicated for the treatment of patients with MM which does not require dose modification in the setting of renal impairment. Real-world data regarding its efficacy in patients with renal impairment and the rate of renal response are lacking. Methods: We performed a retrospective, single-center analysis of patients with relapsed/refractory MM treated with daratumumab as monotherapy or in combination with novel agents. Patients were grouped by renal function as calculated by their eGFR using the MDRD equation: <30, 30-59, >=60 mL/min/1.73m2. Renal response was defined as an eGFR >= 60 in two consecutive visits for patients with baseline renal impairment. Results: We identified 91 patients who started treatment with daratumumab between 2015-06-11 and 2018-08-16. The median age was 69 years old (range 40-93) and 25% were over the age of 75; 49 patients (54%) were female. Six patients (9%) were Hispanic, 16 (20%) were African American and 57 (71%) were Caucasian. High-risk cytogenetics were present in 58% of patients; defined as the presence of a complex karyotype, 1q gain, t(4;14), t(14;16), t(14;20) or del17p. Patients underwent a median of 5 prior lines of therapy (range 1-13), 45% had received an autologous stem cell transplant, 91% had been exposed to an immunomodulatory agent, 96% to a proteasome inhibitor, and 89% to both. Upon initial treatment, 53 patients (58%) had an eGFR >=60 mL/min/1.73m2, while 27 (30%) and 11 (12%) patients had an eGFR of 30-59 and <30 mL/min/1.73m2, respectively. The overall response rate (ORR) was 81% with a very good partial response (VGPR) or better of 47% and an unconfirmed complete response rate (uCR) of 23%. The median progression-free survival (mPFS) was 17.5 months while median overall survival (mOS) was not reached. There was no difference in mPFS or mOS between renal function groups. Of the 38 patients with baseline renal impairment (eGFR <60 mL/min/1.73m2), 11 patients (29%) achieved a renal response, however, none of these patients had severe renal impairment. When compared to patients with chronic renal impairment, those with acute renal impairment were more likely to achieve a renal response (80% vs 21%, p=0.02). No significant difference in mPFS or mOS was observed by renal response (mPFS: 25.7m vs 17.5m, p=0.2; mOS: NR vs NR, p=0.8). Each renal function group was well balanced for the above parameters, including adverse events of interest and concurrent myeloma therapy as shown in the table, except where indicated (*). Discussion: The results of this analysis provide comparable efficacy - independent of the degree of baseline renal impairment - to the results seen in clinical trials of combination therapy with daratumumab. Furthermore, the high renal response rate (29%) seen, as compared to the one in the subgroup analysis of ENDEAVOR (15%), highlights the utility of daratumumab in reversing renal end-organ damage in patients with relapsed/refractory MM without an increase in adverse events compared to patients with preserved renal function. These results suggest that daratumumab may be able to abrogate the adverse prognostic factor that impaired baseline renal function portends. A limitation of this study is its retrospective nature, the confounding effect of concurrent myeloma therapy and the small number of patients included with renal impairment. Table Disclosures Coleman: Merck: Research Funding; Pharmacyclics: Speakers Bureau; Kite Pharmaceuticals: Equity Ownership; Gilead, Bayer, Celgene: Consultancy, Research Funding, Speakers Bureau. Niesvizky:Takeda, Amgen, BMS, Janssen, Celgene: Consultancy, Research Funding. Rossi:Janssen, Celgene, Amgen: Consultancy; BMS: Research Funding.