Background: Myeloma causes profound immunodeficiency and recurrent serious infections. There are approximately 5500 new UK cases of myeloma per annum, and one-quarter of patients will have a serious infection within 3 months of diagnosis. Newly diagnosed patients may benefit from antibiotic prophylaxis to prevent infection. However, the use of prophylaxis has not been established in myeloma and may be associated with health-care-associated infections (HCAIs), such as Clostridium difficile. There is a need to assess the benefits and cost-effectiveness of the use of antibacterial prophylaxis against any risks in a double-blind, placebo-controlled, randomised clinical trial.
Objectives: To assess the risks, benefits and cost-effectiveness of prophylactic levofloxacin in newly diagnosed symptomatic myeloma patients.
Design: Multicentre, randomised, double-blind, placebo-controlled trial. A central telephone randomisation service used a minimisation computer algorithm to allocate treatments in a 1 : 1 ratio.
Setting: A total of 93 NHS hospitals throughout England, Northern Ireland and Wales.
Participants: A total of 977 patients with newly diagnosed symptomatic myeloma.
Intervention: Patients were randomised to receive levofloxacin or placebo tablets for 12 weeks at the start of antimyeloma treatment. Treatment allocation was blinded and balanced by centre, estimated glomerular filtration rate and intention to give high-dose chemotherapy with autologous stem cell transplantation. Follow-up was at 4-week intervals up to 16 weeks, with a further follow-up at 1 year.
Main outcome measures: The primary outcome was to assess the number of febrile episodes (or deaths) in the first 12 weeks from randomisation. Secondary outcomes included number of deaths and infection-related deaths, days in hospital, carriage and invasive infections, response to antimyeloma treatment and its relation to infection, quality of life and overall survival within the first 12 weeks and beyond.
Results: In total, 977 patients were randomised (levofloxacin, n = 489; placebo, n = 488). A total of 134 (27%) events (febrile episodes, n = 119; deaths, n = 15) occurred in the placebo arm and 95 (19%) events (febrile episodes, n = 91; deaths, n = 4) occurred in the levofloxacin arm; the hazard ratio for time to first event (febrile episode or death) within the first 12 weeks was 0.66 (95% confidence interval 0.51 to 0.86; p = 0.002). Levofloxacin also reduced other infections (144 infections from 116 patients) compared with placebo (179 infections from 133 patients; p-trend of 0.06). There was no difference in new acquisitions of C. difficile, methicillin-resistant Staphylococcus aureus and extended-spectrum beta-lactamase Gram-negative organisms when assessed up to 16 weeks. Levofloxacin produced slightly higher quality-adjusted life-year gains over 16 weeks, but had associated higher costs for health resource use. With a median follow-up of 52 weeks, there was no significant difference in overall survival (p = 0.94).
Limitations: Short duration of prophylactic antibiotics and cost-effectiveness.
Conclusions: During the 12 weeks from new diagnosis, the addition of prophylactic levofloxacin to active myeloma treatment significantly reduced febrile episodes and deaths without increasing HCAIs or carriage. Future work should aim to establish the optimal duration of antibiotic prophylaxis and should involve the laboratory investigation of immunity, inflammation and disease activity on stored samples funded by the TEAMM (Tackling Early Morbidity and Mortality in Myeloma) National Institute for Health Research Efficacy and Mechanism Evaluation grant (reference number 14/24/04).
Trial registration: Current Controlled Trials ISRCTN51731976.
Funding details: This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 62. See the NIHR Journals Library website for further project information.
Keywords: ANTIBIOTIC PROPHYLAXIS; HEALTH-CARE-ASSOCIATED INFECTIONS; INFECTION; MYELOMA; SURVIVAL.
What is the problem?: Myeloma is a type of cancer that develops from cells in the bone marrow, called plasma cells, which are part of the immune system. Because myeloma affects the immune system, people who have it are at greater risk of picking up infections. This risk is higher at the start of antimyeloma therapy when the myeloma is active.
What did the study do?: The trial looked to see if the risk of getting an infection can be reduced, rather than waiting to see if an infection developed and then treating it. An antibiotic already used all over the world, called levofloxacin was tested. Half of the patients (n = 489) took levofloxacin for 12 weeks and the other half (n = 488) were given a dummy tablet (placebo). The aim was to see if taking levofloxacin at the start of antimyeloma therapy reduced the risk of getting an infection. Alongside this, we evaluated three important groups of antibiotic-resistant bacteria to see whether or not the use of preventative levofloxacin increased the number of these resistant bacteria living in the body. In addition, the overall survival, economic impacts and the impact of using preventative antibiotics on patients’ quality of life and response to antimyeloma treatment were evaluated.
What did the study find?: During the 12 weeks from new diagnosis of myeloma, the addition of prophylactic levofloxacin to active myeloma treatment significantly reduced the number of febrile episodes and deaths [134 (febrile episodes alone, n = 112; febrile episodes plus death, n = 7; deaths alone, n = 15) out of 488 (27%) placebo patients vs. 95 (febrile episodes alone, n = 87; febrile episodes plus death, n = 4; deaths alone, n = 4) out of 489 (19%) levofloxacin patients; p = 0.002] without increasing antibiotic-resistant bacteria.