Reduction in C-reactive protein indicates successful targeting of the IL-1/IL-6 axis resulting in improved survival in early stage multiple myeloma.

We report the long-term follow-up results of a phase II trial of IL-1 receptor antagonist and low-dose dexamethasone for early stage multiple myeloma (MM). Patients were eligible if they had smoldering multiple myeloma (SMM) or indolent multiple myeloma (IMM) without the need for immediate therapy. Forty seven patients were enrolled and subsequently treated with IL-1Ra; in 25/47 low-dose dexamethasone (20 mg weekly) was added. The primary endpoint was progression-free survival (PFS). In the clinical trial, three patients achieved a minor response (MR) to IL-1Ra alone; five patients a partial response (PR) and four patients an MR after addition of dexamethasone. Seven patients showed a decrease in the plasma cell labeling index (PCLI) which paralleled a decrease in the high sensitivity C-reactive protein (hs-CRP). The median PFS for the 47 patients was 1116 days (37.2 months). The median PFS for patients without (n = 22) and with (n = 25) a decrease in their baseline hs-CRP was 326 days (11 months) vs. 3139 days (104 months) respectively (P <0.0001). The median overall survival (OS) for the 47 patients was 3482 days (9.5 years). The median OS for patients without and with a decrease in their baseline hs-CRP was 2885 days (7.9 years) vs. median not reached, respectively (P = 0.001). In SMM/IMM patients at risk for progression to active myeloma, reduction in the hs-CRP indicates successful targeting of the IL-1/IL-6 axis resulting in improved PFS and OS. (Clinical Trials.gov Identifier: NCT00635154) Am. J. Hematol. 91:571-574, 2016. © 2016 Wiley Periodicals, Inc.

Induction of a chronic disease state in patients with smoldering or indolent multiple myeloma by targeting interleukin 1{beta}-induced interleukin 6 production and the myeloma proliferative component.

OBJECTIVE: To conduct in vitro studies as well as a phase 2 clinical trial in patients with smoldering or indolent multiple myeloma to determine if interleukin 1 (IL-1) inhibitors can delay or prevent active myeloma. PATIENTS AND METHODS: Stromal cells were cocultured with IL-1beta-expressing myeloma cells in the presence of dexamethasone, IL-1 receptor antagonist (IL-1Ra), or both. Levels of interleukin 6 (IL-6) and of apoptosis were also quantified. Between November 19, 2002, and May 24, 2007, 47 patients were enrolled in the study and subsequently treated with IL-1Ra. In 25 (53%) of the 47 study patients, low-dose dexamethasone (20 mg/wk) was added. The primary end point was progression-free survival (PFS). RESULTS: In vitro, IL-1Ra was superior to dexamethasone at inhibiting IL-6 production; maximal IL-6 inhibition and apoptosis induction were achieved by addition of both IL-1Ra and dexamethasone. In the clinical trial, 3 patients achieved a minor response to IL-1Ra alone; 5 patients achieved a partial response and 4 patients a minor response after addition of dexamethasone. Seven patients showed a decrease in the plasma cell labeling index that paralleled a decrease in high-sensitivity C-reactive protein (hs-CRP) levels. The median overall PFS was 37.5 months. The median PFS for patients without (n=12) or with (n=35) a greater than 15% decrease in 6-month vs baseline hs-CRP levels was 6 months and more than 3 years, respectively (P=.002). Disease stability was maintained in 8 patients who received therapy for more than 4 years. CONCLUSION: In patients with smoldering or indolent multiple myeloma who were at risk of progression to active myeloma, treatment with IL-1 inhibitors decreased the myeloma proliferative rate and hs-CRP levels in those who responded, leading to a chronic disease state and an improved PFS. TRIAL REGISTRATION: clinicaltrials.gov identifier: NCT00635154.

Identification of two groups of smoldering multiple myeloma patients who are either high or low producers of interleukin-1.

Interleukin-1beta (IL-1beta) is abnormally expressed by the plasma cells obtained from myeloma patients, and it is a potent inducer of the important myeloma growth factor, IL-6. We investigated whether levels of IL-1beta biologic activity might distinguish different groups of patients with smoldering multiple myeloma (SMM). We measured the ability of IL-6 production by bone marrow stromal cells to serve as a surrogate marker for IL-1beta biologic activity. Using this IL-1beta bioassay, we found that it is sensitive at < 1 pg/ml of recombinant IL-1beta and that IL-1beta biologic activity is detectable with either mature or pro-IL-1beta-transduced myeloma cell lines. Patients with active myeloma induced quantitatively higher levels of stromal cell IL-6 production when compared with those with monoclonal gammopathy of undetermined significance (MGUS). The bioassay distinguished two groups of SMM patients, those who were high producers, similar to patients with active MM, and those who were low producers, comparable to MGUS patients. IL-1 antagonists inhibited the paracrine IL-6 production by > or = 90% in the majority of patients with an elevated IL-6 level. Based on such studies, it may be possible to predict patients that will progress to active MM and to delay or prevent this progression with IL-1 antagonists.