Long-term disease control by pomalidomide-/dexamethasone-based therapy in a patient with advanced multiple myeloma: a case report and review of the literature

Elotuzumab, pomalidomide, and dexamethasone is a very well tolerated regimen associated with durable remission even in very advanced myeloma: a retrospective study from two academic centers

Background

The anti-SLAMF7 monoclonal antibody, elotuzumab (elo), plus lenalidomide (len) and dexamethasone (dex) is approved for relapsed/refractory MM in the U.S. and Europe. Recently, a small phase 2 study demonstrated an advantage in progression-free survival (PFS) for elo plus pomalidomide (pom)/dex compared to pom/dex alone and resulted in licensing of this novel triplet combination, but clinical experience is still limited.

Purpose

To analyze the efficacy and safety of elo/pom/dex in a “real world” cohort of patients with advanced MM, we queried the databases of the university hospitals of Würzburg and Vienna.

Findings

We identified 22 patients with a median number of five prior lines of therapy who received elo/pom/dex prior to licensing within an early access program. Patients received a median number of 5 four-week treatment cycles. Median PFS was 6.4 months with 12-month and 18-month PFS rates of 35% and 28%, respectively. The overall response rate was 50% and 64% of responding patients who achieved a longer PFS with elo/pom/dex compared to their most recent line of therapy. Objective responses were also seen in five patients who had been pretreated with pomalidomide. Low tumor burden was associated with improved PFS (13.5 months for patients with ISS stage I/II at study entry v 6.4 months for ISS III), although this difference did not reach statistical significance. No infusion-related reactions were reported. The most frequent grade 3/4 adverse events were neutropenia and pneumonia.

Conclusion

Elo/pom/dex is an active and well-tolerated regimen in highly advanced MM even after pretreatment with pomalidomide.

Reactivation of Hepatitis B Virus in Patients with Multiple Myeloma

Reactivation of hepatitis B virus (HBV) is a well-known complication in patients with hematological malignancies during or after cytotoxic chemotherapy. If the initiation of antiviral therapy is delayed in patients with HBV reactivation, these patients can develop severe hepatitis and may die of fulminant hepatitis. The preventive strategy for HBV reactivation in patients with malignant lymphoma has already been established based on some prospective studies. As there was an increased number of novel agents being approved for the treatment of multiple myeloma (MM), the number of reported cases of HBV reactivation among MM patients has gradually increased. We conducted a Japanese nationwide retrospective study and revealed that HBV reactivation in MM patients is not rare and that autologous stem cell transplantation is a significant risk factor. In this study, around 20% of all patients with HBV reactivation developed HBV reactivation after 2 years from the initiation of therapy, unlike malignant lymphoma. This might be due to the fact that almost all of the patients received chemotherapy for a long duration. Therefore, a new strategy for the prevention of HBV reactivation in MM patients is required.

Screening and Prophylaxis to Prevent Hepatitis B Reactivation: Other Populations and Newer Agents

Because of the relatively high prevalence of both hepatitis B infection and various forms of autoimmune inflammatory diseases treated with aggressive immunotherapy, reactivation of hepatitis B occurs in a substantial number of patients. The risk of reactivation depends on the degree and duration of immunosuppression. A large number of drug treatments have resulted in reactivation of hepatitis B virus infection and, based on the mechanisms and extent of immunosuppression, recommendations for some of the newer classes of immunosuppressive drugs are provided.

Prevention and management of hepatitis B virus reactivation in patients with hematological malignancies treated with anticancer therapy

Hepatitis due to hepatitis B virus (HBV) reactivation can be severe and potentially fatal, but is preventable. HBV reactivation is most commonly reported in patients receiving cancer chemotherapy, especially rituximab-containing therapy for hematological malignancies and those receiving stem cell transplantation. All patients with hematological malignancies receiving anticancer therapy should be screened for active or resolved HBV infection by blood tests for hepatitis B surface antigen (HBsAg) and antibody to hepatitis B core antigen (anti-HBc). Patients found to be positive for HBsAg should be given prophylactic antiviral therapy to prevent HBV reactivation. For patients with resolved HBV infection, no standard strategy has yet been established to prevent HBV reactivation. There are usually two options. One is pre-emptive therapy guided by serial HBV DNA monitoring, whereby antiviral therapy is given as soon as HBV DNA becomes detectable. However, there is little evidence regarding the optimal interval and period of monitoring. An alternative approach is prophylactic antiviral therapy, especially for patients receiving high-risk therapy such as rituximab, newer generation of anti-CD20 monoclonal antibody, obinutuzumab or hematopoietic stem cell transplantation. This strategy may effectively prevent HBV reactivation and avoid the inconvenience of repeated HBV DNA monitoring. Entecavir or tenofovir are preferred over lamivudine as prophylactic therapy. Although there is no well-defined guideline on the optimal duration of prophylactic therapy, there is growing evidence to recommend continuing prophylactic antiviral therapy for at least 12 mo after cessation of chemotherapy, and even longer for those who receive rituximab or who had high serum HBV DNA levels before the start of immunosuppressive therapy. Many novel agents have recently become available for the treatment of hematological malignancies, and these agents may be associated with HBV reactivation. Although there is currently limited evidence to guide the optimal preventive measures, we recommend antiviral prophylaxis in HBsAg-positive patients receiving novel treatments, especially the Bruton tyrosine kinase inhibitors and the phosphatidylinositol 3-kinase inhibitors, which are B-cell receptor signaling modulators and reduce proliferation of malignant B-cells. Further studies are needed to clarify the risk of HBV reactivation with these agents and the best prophylactic strategy in the era of targeted therapy for hematological malignancies.

Incidence and clinical background of hepatitis B virus reactivation in multiple myeloma in novel agents' era

There are some reports regarding hepatitis B virus (HBV) reactivation in patients with myeloma who are HBV carriers or who have had a resolved HBV infection, and there is no standard prophylaxis strategy for these patients. We performed a retrospective multicenter study to determine the incidence and characteristics of HBV reactivation in patients with multiple myeloma. We identified 641 patients with multiple myeloma who had been treated using novel agents and/or autologous stem cell transplantation with high-dose chemotherapy between January 2006 and June 2014 at nine Japanese hospitals. The patients' characteristics, laboratory data, and clinical courses were retrieved and statistically analyzed. During a median follow-up of 101 weeks, one of eight (12.5 %) HBV carriers developed hepatitis and 9 of 99 (9.1 %) patients with resolved HBV infection experienced HBV reactivation; the cumulative incidences of HBV reactivation at 2 years (104 weeks) and 5 years (260 weeks) were 8 and 14 %, respectively. The nine cases of reactivation after resolved HBV infection had received entecavir as preemptive therapy or were carefully observed by monitoring their HBV DNA levels, and none of these cases developed hepatitis. Among patients with multiple myeloma, HBV reactivation was not rare. Therefore, long-term monitoring of HBV DNA levels is needed to prevent hepatitis that is related to HBV reactivation in these patients.

Long-term disease control in a refractory multiple myeloma patient treated with bortezomib mono-therapy: a case report and review of literature

Multiple myeloma (MM) accounts for 1.5% of all cancers and approximately 13% of all hematologic malignancies. Therapy for MM has substantially improved after the application of immunomodulatory drugs and proteasome inhibitors. The first proteasome inhibitor, bortezomib, can be considered a major milestone in treatment of MM, greatly improving the response rates and overall survival in front-line and relapsed/refractory settings. However, the prognosis of patients with progressive disease remains poor. In this article, we report a case of refractory MM patient who gained a long time disease control by bortezomib mono-therapy and do a critical review of the literature. We aim to share our experience of efficiency and safety of the long term mono-therapy of bortezomib in a refractory MM.