{"product_id":"infections-after-car-t-cell-therapy-and-bispecific-antibodies-in-multiple-myeloma-what-patients-need-to-know","title":"Infections After CAR-T Cell Therapy and Bispecific Antibodies in Multiple Myeloma: What Patients Need to Know","description":"\u003cp\u003eThis systematic review analyzed 123 studies of two modern multiple myeloma treatments — CAR-T cell therapy and bispecific antibodies — and found that infections are very common in patients receiving either treatment. Any-grade infections occurred in roughly 40–80% of patients, and severe infections (grade 3 or higher) exceeded 50% in several bispecific antibody studies. Risk was highest early after CAR-T infusion and during the first months of bispecific antibody therapy. Risk factors included low white blood cell counts, corticosteroid and tocilizumab exposure, and low antibody levels. Antiviral and antibiotic prophylaxis, along with immunoglobulin replacement, reduced infections, but some risk remained.\u003c\/p\u003e\n\n\u003ch1\u003eInfections After CAR-T Cell Therapy and Bispecific Antibodies in Multiple Myeloma: What Patients Need to Know\u003c\/h1\u003e\n\n\u003ch2\u003eTable of Contents\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"#ddn-key-points\"\u003eKey Points\u003c\/a\u003e\u003c\/li\u003e\n\n  \u003cli\u003e\u003ca href=\"#background\"\u003eBackground: Why This Research Matters\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#methods\"\u003eHow the Research Was Conducted\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#quality\"\u003eStudy Quality and Risk of Bias\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#teclistamab\"\u003eFindings for Teclistamab\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#elranatamab\"\u003eFindings for Elranatamab\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#talquetamab\"\u003eFindings for Talquetamab\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#car-t\"\u003eFindings for CAR-T Cell Therapies\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#comparison\"\u003eComparing Infections Across Treatments\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#pathogens\"\u003eWhich Pathogens Cause Infections\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#risk-factors\"\u003eRisk Factors for Infection\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#prevention\"\u003ePrevention Strategies\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#dosing\"\u003eExtended Dosing Intervals\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#implications\"\u003eWhat This Means for Patients\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#limitations\"\u003eLimitations of the Research\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#recommendations\"\u003eRecommendations\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"#ddn-faq\"\u003eFrequently Asked Questions\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#source\"\u003eSource Information\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003c!-- ddn:keypoints:start --\u003e\n\u003ch2 id=\"ddn-key-points\"\u003eKey Points\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eIn a review of 123 studies, any-grade infections occurred in roughly 40–80% of patients receiving CAR-T cell therapy or bispecific antibodies for multiple myeloma.\u003c\/li\u003e\n\u003cli\u003eSevere infections (grade 3 or higher) exceeded 50% in several bispecific antibody studies and ranged from 4.2% to 34% across CAR-T cell studies.\u003c\/li\u003e\n\u003cli\u003eRisk was highest early after CAR-T infusion and during the first months of bispecific antibody therapy, with some risk persisting over time.\u003c\/li\u003e\n\u003cli\u003eKey risk factors included low white blood cell counts, corticosteroid and tocilizumab exposure, and low antibody levels (hypogammaglobulinemia).\u003c\/li\u003e\n\u003cli\u003eAntiviral, PJP, antibacterial, and antifungal prophylaxis plus immunoglobulin replacement reduced infections, and extended dosing intervals may lower severe infections.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- ddn:keypoints:end --\u003e\n\n\n\u003ch2 id=\"background\"\u003eBackground: Why This Research Matters\u003c\/h2\u003e\n\n\u003cp\u003eMultiple myeloma (a cancer of plasma cells in the bone marrow) has seen a major shift in treatment. After monoclonal antibodies were introduced, two newer types of immunotherapy became central to treating relapsed or refractory multiple myeloma (RRMM). These two newer types of immunotherapy are bispecific antibodies (BsAbs) and CAR-T cell therapy. RRMM means the cancer has returned or stopped responding to prior treatments.\u003c\/p\u003e\n\n\u003cp\u003eBoth treatment types produce deep responses against the cancer. However, they also cause prolonged immune system disruption. This makes infections a major cause of illness, death, and increased healthcare use.\u003c\/p\u003e\n\n\u003cp\u003eSeveral factors contribute to this weakened immune state:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003ePersistent low blood cell counts (cytopenias)\u003c\/li\u003e\n  \u003cli\u003eB-cell aplasia (loss of antibody-producing B cells)\u003c\/li\u003e\n  \u003cli\u003eHypogammaglobulinemia (low levels of protective antibodies)\u003c\/li\u003e\n  \u003cli\u003eImpairment of both innate and adaptive immune compartments\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eDespite the growing use of these therapies, a systematic, infection-focused summary has been limited. This summary would cover how often infections occur, when infections occur, how severe infections are, what causes infections, and how to prevent infections. This review was designed to fill that gap.\u003c\/p\u003e\n\n\u003cp\u003eThe authors also noted an important practical difference between the two treatment types. CAR-T cell therapy is resource-intensive and requires complex logistics. Bispecific antibodies are given continuously in most current regimens, which may prolong the period of infection risk related to ongoing exposure.\u003c\/p\u003e\n\n\u003cp\u003eDirect head-to-head comparisons between CAR-T and bispecific antibodies are currently lacking. However, emerging real-world data suggest there may be differences in infection profiles and toxicity severity between the two approaches.\u003c\/p\u003e\n\n\u003ch2 id=\"methods\"\u003eHow the Research Was Conducted\u003c\/h2\u003e\n\n\u003cp\u003eThis review followed PRISMA 2020 guidelines, which are internationally recognized standards for conducting and reporting systematic reviews.\u003c\/p\u003e\n\n\u003cp\u003eThe researchers searched PubMed\/MEDLINE through May 22, 2026. They included randomized trials, cohort studies, and real-world studies that reported infectious outcomes in patients with multiple myeloma treated with CAR-T cells or bispecific antibodies.\u003c\/p\u003e\n\n\u003cp\u003eStudies were excluded if they involved:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eCancers other than multiple myeloma\u003c\/li\u003e\n  \u003cli\u003eNo reported infectious outcomes\u003c\/li\u003e\n  \u003cli\u003eTreatments other than CAR-T cells or bispecific antibodies\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eReviews, meta-analyses, case reports, and editorials were also excluded, as were studies without extractable infection data.\u003c\/p\u003e\n\n\u003cp\u003eScreening and data extraction were performed independently by two reviewers (MB and NS), with consensus resolution by a third reviewer (TW).\u003c\/p\u003e\n\n\u003cp\u003eThe search strategy combined terms for the disease (\"multiple myeloma\"), the treatments (\"CAR-T,\" \"bispecific antibody,\" teclistamab, elranatamab, linvoseltamab, talquetamab, cevostamab, cilta-cel, ide-cel), and the outcome (\"infection\").\u003c\/p\u003e\n\n\u003cp\u003eThe included studies were highly heterogeneous, meaning the studies varied widely in design, patient populations, and reporting methods. Because of this heterogeneity, the researchers decided that a quantitative meta-analysis was not appropriate. A quantitative meta-analysis is a statistical pooling of results. Instead, results are presented narratively by treatment modality and by individual agent.\u003c\/p\u003e\n\n\u003cp\u003eLanguage editing was performed using AI tools (DeepL, ChatGPT) and professional editing services. The authors state they are solely responsible for the scientific content.\u003c\/p\u003e\n\n\u003ch2 id=\"quality\"\u003eStudy Quality and Risk of Bias\u003c\/h2\u003e\n\n\u003cp\u003eThe researchers assessed the methodological quality of each included study using CASP checklists (Critical Appraisal Skills Programme), with separate versions for randomized controlled trials and cohort studies.\u003c\/p\u003e\n\n\u003cp\u003eLower CASP scores reflected several common issues:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eNon-comparative study designs\u003c\/li\u003e\n  \u003cli\u003eSmall patient cohorts\u003c\/li\u003e\n  \u003cli\u003eShort follow-up periods\u003c\/li\u003e\n  \u003cli\u003eIncomplete reporting of patient dropouts and confounder control\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eNo study met criteria for low completeness (below 33%). Studies were categorized as intermediate (34–66% of criteria fulfilled) or high completeness (67% or more).\u003c\/p\u003e\n\n\u003cp\u003eRisk of bias was evaluated using RoB 2 for randomized trials and ROBINS-I for non-randomized studies. Overall judgments followed the \"worst-domain\" principle, meaning the worst rating in any single domain determined the overall rating.\u003c\/p\u003e\n\n\u003cp\u003eOverall risk of bias was often rated as serious. This was mainly due to confounding and selection bias, which are inherent to early-phase, single-arm studies. Other domains were rated low to moderate, indicating generally robust conduct within those areas.\u003c\/p\u003e\n\n\u003ch2 id=\"teclistamab\"\u003eFindings for Teclistamab\u003c\/h2\u003e\n\n\u003cp\u003eThe review included seven early-phase trial reports, one phase III trial, and fifteen real-world cohort studies of teclistamab.\u003c\/p\u003e\n\n\u003cp\u003eAn extended safety analysis of the MajesTEC-1 trial reported infections in 80% of patients. Respiratory tract infections were most common, occurring in 19.4% of patients. The infection-related mortality rate was 12.7%.\u003c\/p\u003e\n\n\u003cp\u003eThe median time to first infection was 1.7 months. Although most infections occurred within the first 30 days, the risk persisted over time.\u003c\/p\u003e\n\n\u003cp\u003eSpecific pathogens reported in the MajesTEC-1 analysis included:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eHerpesviruses: 4.2%\u003c\/li\u003e\n  \u003cli\u003eCMV (cytomegalovirus) reactivation: 1.2%\u003c\/li\u003e\n  \u003cli\u003ePJP (Pneumocystis jirovecii pneumonia): 4.2%\u003c\/li\u003e\n  \u003cli\u003eFungal infections: 5.5%\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eThe phase III MajesTEC-3 trial confirmed the substantial infectious burden associated with BCMA-directed bispecific antibody therapy when used in earlier treatment lines. In that trial, infections occurred in 96.5% of patients, grade 3–4 infections occurred in 54.1%, and fatal infections occurred in 4.6%.\u003c\/p\u003e\n\n\u003cp\u003eMost infection-related deaths occurred within the first six months of therapy. The incidence of new severe infections declined after patients transitioned to monthly dosing and reinforced immunoglobulin replacement strategies.\u003c\/p\u003e\n\n\u003cp\u003eReal-world data confirmed infection rates of 42–60%, with serious infections in 22% to 42.9%. In real-world settings, 13% of patients discontinued treatment due to infection, and 30% required hospitalization.\u003c\/p\u003e\n\n\u003cp\u003eInfections in real-world cohorts were predominantly viral (50%) and bacterial (45%). Opportunistic infections occurred less frequently, including fungal infections (5%) and CMV reactivation (22%).\u003c\/p\u003e\n\n\u003cp\u003eInfections remain the leading cause of treatment discontinuation in the real-world setting.\u003c\/p\u003e\n\n\u003cp\u003eThe authors noted that cohorts were consistently heavily pretreated but heterogeneous in recruitment and design. Prospective trials applied CTCAE (Common Terminology Criteria for Adverse Events) reporting standards, whereas real-world studies were retrospective. This contributed to differences in how low-grade events were captured.\u003c\/p\u003e\n\n\u003ch2 id=\"elranatamab\"\u003eFindings for Elranatamab\u003c\/h2\u003e\n\n\u003cp\u003eAcross the elranatamab studies included in this review, any-grade infections ranged from 44% to 74.5%. Grade 3 or higher infections ranged from 18.7% to 34.5%.\u003c\/p\u003e\n\n\u003cp\u003eHypogammaglobulinemia (low antibody levels) was reported in 47.5% to 94.6% of patients. This is a key risk factor for infection.\u003c\/p\u003e\n\n\u003cp\u003eOther reported infection types included:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eViral infections other than CMV and herpesviruses: 5.7% to 10.8%\u003c\/li\u003e\n  \u003cli\u003eCMV reactivation: 3% to 4.9%\u003c\/li\u003e\n  \u003cli\u003eFungal infections: up to 7%\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2 id=\"talquetamab\"\u003eFindings for Talquetamab\u003c\/h2\u003e\n\n\u003cp\u003eTalquetamab showed lower infection rates compared with BCMA-targeted therapies, with any-grade infections ranging from 47% to 55%. However, it was associated with relevant mucocutaneous toxicity (side effects affecting the skin and mucous membranes).\u003c\/p\u003e\n\n\u003cp\u003eGrade 3 or higher infections ranged from 16.7% to 48% across the talquetamab studies. Hypogammaglobulinemia was reported in 23% to 49% of patients.\u003c\/p\u003e\n\n\u003cp\u003eSpecific infection types included:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eViral infections other than CMV and herpesviruses: 1% to 11%\u003c\/li\u003e\n  \u003cli\u003eCMV reactivation: 0%\u003c\/li\u003e\n  \u003cli\u003eFungal infections: 2% to 2.9%\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2 id=\"car-t\"\u003eFindings for CAR-T Cell Therapies\u003c\/h2\u003e\n\n\u003cp\u003eThe review included studies of two BCMA-directed CAR-T cell products: ide-cel (idecabtagene vicleucel) and cilta-cel (ciltacabtagene autoleucel).\u003c\/p\u003e\n\n\u003cp\u003eFor ide-cel, any-grade infections ranged from 44% to 78.8%. Grade 3 or higher infections ranged from 8% to 20%. Hypogammaglobulinemia was reported in 12% to 23%.\u003c\/p\u003e\n\n\u003cp\u003eFor cilta-cel, any-grade infections ranged from 58.4% to 100%. Grade 3 or higher infections ranged from 11.1% to 34%. Hypogammaglobulinemia was reported in 20% to 70%.\u003c\/p\u003e\n\n\u003cp\u003eAcross all CAR-T cell studies combined, any-grade infections ranged from 30.6% to 61%. Grade 3 or higher infections ranged from 4.2% to 24%. Hypogammaglobulinemia occurred frequently after BCMA-directed CAR-T therapy (80%).\u003c\/p\u003e\n\n\u003cp\u003eIn randomized CAR-T trials, grade 5 infections (fatal infections) represented a substantial proportion of treatment-related deaths.\u003c\/p\u003e\n\n\u003cp\u003eOne real-world study comparing CAR-T and bispecific antibodies found infection rates of 20% for CAR-T versus 24% for bispecific antibodies. Another study reported 50% for CAR-T versus 44% for bispecific antibodies. A third study reported 60% for CAR-T versus 49% for bispecific antibodies.\u003c\/p\u003e\n\n\u003cp\u003eAnother real-world analysis found grade 3 or higher infection rates of 19% for CAR-T versus 76% for bispecific antibodies. A separate study reported 8% for PGPRD5 bispecific antibodies versus 19% for BCMA bispecific antibodies.\u003c\/p\u003e\n\n\u003ch2 id=\"comparison\"\u003eComparing Infections Across Treatments\u003c\/h2\u003e\n\n\u003cp\u003eThe review found that infections were frequent across all BCMA-directed CAR-T products and bispecific antibodies, with any-grade incidence of approximately 40–80%.\u003c\/p\u003e\n\n\u003cp\u003eThe highest risk occurred early after CAR-T infusion and during the first months of bispecific antibody therapy.\u003c\/p\u003e\n\n\u003cp\u003eGrade 3 or higher infections were common and exceeded 50% in several bispecific antibody cohorts. Fatal infections were less frequent but occurred across both CAR-T and bispecific antibody studies.\u003c\/p\u003e\n\n\u003cp\u003eReal-world data suggest higher infection-related healthcare use and mortality with bispecific antibodies compared with CAR-T therapy. However, the authors caution that direct comparative data are currently lacking, and these differences may reflect differences in patient populations and treatment settings.\u003c\/p\u003e\n\n\u003ch2 id=\"pathogens\"\u003eWhich Pathogens Cause Infections\u003c\/h2\u003e\n\n\u003cp\u003eViral and bacterial pathogens predominated across the studies. The most commonly reported pathogens included:\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eViral infections:\u003c\/strong\u003e Herpesviruses (including HSV and VZV), CMV reactivation, and other viral pathogens\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBacterial infections:\u003c\/strong\u003e Respiratory tract infections were most common\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFungal infections:\u003c\/strong\u003e Invasive fungal infections were reported, particularly in patients not receiving antifungal prophylaxis\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePneumocystis jirovecii pneumonia (PJP):\u003c\/strong\u003e Reported particularly in patients without PJP prophylaxis\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eCMV reactivation was a notable concern, with rates ranging from 0% to 22% depending on the treatment and study population.\u003c\/p\u003e\n\n\u003ch2 id=\"risk-factors\"\u003eRisk Factors for Infection\u003c\/h2\u003e\n\n\u003cp\u003eThe review identified several key risk factors that increased the likelihood of infection in patients receiving CAR-T cell therapy or bispecific antibodies:\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eNeutropenia\u003c\/strong\u003e (low levels of neutrophils, a type of white blood cell that fights infection)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCorticosteroid exposure\u003c\/strong\u003e (steroid medications that suppress the immune system)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eTocilizumab exposure\u003c\/strong\u003e (a medication used to treat cytokine release syndrome, a common side effect of immunotherapy)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHypogammaglobulinemia\u003c\/strong\u003e (low levels of protective antibodies)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003ePersistent cytopenias (low blood cell counts that continue over time) and B-cell aplasia (loss of antibody-producing B cells) also contributed to immunosuppression.\u003c\/p\u003e\n\n\u003cp\u003eThe authors noted that risk is particularly high with BCMA-targeted therapies and continuous bispecific antibody administration.\u003c\/p\u003e\n\n\u003ch2 id=\"prevention\"\u003ePrevention Strategies\u003c\/h2\u003e\n\n\u003cp\u003eThe review found that several prevention strategies reduced infections, though residual risk persisted.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eAntiviral prophylaxis\u003c\/strong\u003e against HSV (herpes simplex virus) and VZV (varicella-zoster virus) became standard alongside PJP prophylaxis. In the dose-finding trial, PJP prophylaxis was initially used in 83% of patients.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eAntibacterial and antifungal prophylaxis\u003c\/strong\u003e during periods of neutropenia was also recommended.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eIntravenous immunoglobulin (IVIG)\u003c\/strong\u003e use increased from 11% to 62% across studies and was associated with fewer severe infections. At 6 months, grade 3\/4 infections occurred in 5.3% of patients receiving IVIG versus a higher rate in those who did not receive it.\u003c\/p\u003e\n\n\u003cp\u003eIn real-world settings, immunoglobulin supplementation was administered to 46% of patients and was associated with improved infection-free survival.\u003c\/p\u003e\n\n\u003cp\u003eThe authors noted that immunoglobulin replacement most notably reduced infections, though the implementations were heterogeneous across clinical trials.\u003c\/p\u003e\n\n\u003ch2 id=\"dosing\"\u003eExtended Dosing Intervals\u003c\/h2\u003e\n\n\u003cp\u003eThe review found evidence that extended dosing intervals may reduce infections, particularly severe infections, while preserving treatment efficacy.\u003c\/p\u003e\n\n\u003cp\u003eIn the MajesTEC-3 trial, the incidence of new severe infections declined after patients transitioned to monthly dosing and reinforced immunoglobulin replacement strategies.\u003c\/p\u003e\n\n\u003cp\u003eThis finding suggests that response-adapted treatment strategies, including extended dosing intervals, may improve safety and outcomes for patients receiving bispecific antibodies.\u003c\/p\u003e\n\n\u003ch2 id=\"implications\"\u003eWhat This Means for Patients\u003c\/h2\u003e\n\n\u003cp\u003eInfectious toxicity remains a key limitation of both CAR-T cell therapy and bispecific antibodies for multiple myeloma. Patients considering these treatments should be aware that infections are common and can be serious.\u003c\/p\u003e\n\n\u003cp\u003eThe risk is particularly high with BCMA-targeted therapies and continuous bispecific antibody administration. However, several strategies can reduce this risk:\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eAntiviral prophylaxis against HSV and VZV\u003c\/li\u003e\n  \u003cli\u003ePJP prophylaxis\u003c\/li\u003e\n  \u003cli\u003eAntibacterial and antifungal prophylaxis during neutropenia\u003c\/li\u003e\n  \u003cli\u003eImmunoglobulin replacement therapy\u003c\/li\u003e\n  \u003cli\u003eExtended dosing intervals when appropriate\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003ePatients should discuss these prevention strategies with their healthcare team before starting treatment. Early immunoglobulin replacement may be particularly important for patients who develop hypogammaglobulinemia.\u003c\/p\u003e\n\n\u003cp\u003eThe authors emphasize that tailored prophylaxis, early immunoglobulin replacement, and response-adapted treatment strategies may improve safety and outcomes for patients receiving these therapies.\u003c\/p\u003e\n\n\u003ch2 id=\"limitations\"\u003eLimitations of the Research\u003c\/h2\u003e\n\n\u003cp\u003eThe authors identified several important limitations of this review:\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHeterogeneity:\u003c\/strong\u003e The included studies varied widely in design, patient populations, and reporting methods, making direct comparisons difficult.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eLack of direct comparative data:\u003c\/strong\u003e No head-to-head randomized trials directly compared infection profiles between CAR-T cell therapy and bispecific antibodies.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRisk of bias:\u003c\/strong\u003e Overall risk of bias was often rated as serious, mainly due to confounding and selection bias inherent to early-phase, single-arm studies.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRetrospective real-world data:\u003c\/strong\u003e Real-world studies were retrospective, which may lead to underreporting of low-grade infections compared with prospective trials using CTCAE reporting.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eShort follow-up:\u003c\/strong\u003e Many studies had short follow-up periods, which may not capture late infections.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSmall cohorts:\u003c\/strong\u003e Some studies included small numbers of patients, limiting the precision of infection rate estimates.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eIncomplete reporting:\u003c\/strong\u003e Some studies did not report attrition or confounder control, and some infection data were not extractable.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eThe authors also noted that the definition of infection outcomes and follow-up duration varied across studies, limiting comparability.\u003c\/p\u003e\n\n\u003ch2 id=\"recommendations\"\u003eRecommendations\u003c\/h2\u003e\n\n\u003cp\u003eBased on the findings of this systematic review, the authors recommend the following:\u003c\/p\u003e\n\n\u003col\u003e\n  \u003cli\u003e\n\u003cstrong\u003eTailored prophylaxis:\u003c\/strong\u003e Patients should receive antiviral prophylaxis against HSV and VZV, PJP prophylaxis, and antibacterial and antifungal prophylaxis during periods of neutropenia.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eEarly immunoglobulin replacement:\u003c\/strong\u003e Immunoglobulin replacement therapy should be considered early, particularly for patients who develop hypogammaglobulinemia.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eResponse-adapted treatment strategies:\u003c\/strong\u003e Extended dosing intervals may reduce infections, particularly severe infections, while preserving efficacy.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCareful patient selection:\u003c\/strong\u003e Given the infection risk, patient selection for CAR-T cell therapy and bispecific antibodies should carefully weigh the benefits against the risks.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMonitoring:\u003c\/strong\u003e Patients should be monitored closely for infections, especially during the early treatment period (first 30 days after CAR-T infusion and first months of bispecific antibody therapy).\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFurther research:\u003c\/strong\u003e Direct comparative studies are needed to better understand differences in infection profiles between CAR-T cell therapy and bispecific antibodies.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003cp\u003eThe authors conclude that infectious toxicity remains a key limitation of these therapies. Risk is particularly high with BCMA-targeted therapies and continuous bispecific antibody administration. Tailored prophylaxis, early immunoglobulin replacement, and response-adapted treatment strategies, including extended dosing intervals, may improve safety and outcomes.\u003c\/p\u003e\n\n\u003c!-- ddn:faq:start --\u003e\n\u003ch2 id=\"ddn-faq\"\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003ch3\u003eHow common are infections with CAR-T cell therapy or bispecific antibodies for multiple myeloma?\u003c\/h3\u003e\n\u003cp\u003eIn the 123 studies reviewed, any-grade infections occurred in roughly 40–80% of patients receiving either treatment. Severe infections (grade 3 or higher) exceeded 50% in several bispecific antibody studies. Risk was highest early after CAR-T infusion and during the first months of bispecific antibody therapy. Fatal infections were less frequent but occurred with both treatment types.\u003c\/p\u003e\n\u003ch3\u003eWhen is the risk of infection highest after starting these treatments?\u003c\/h3\u003e\n\u003cp\u003eThe review found that risk was highest early after CAR-T infusion and during the first months of bispecific antibody therapy. For teclistamab, the median time to first infection was 1.7 months, and most infections occurred within the first 30 days, though risk persisted over time. In one phase III trial, most infection-related deaths occurred within the first six months.\u003c\/p\u003e\n\u003ch3\u003eWhat factors increase the risk of infection during these treatments?\u003c\/h3\u003e\n\u003cp\u003eKey risk factors identified were low white blood cell counts (neutropenia), corticosteroid exposure, tocilizumab exposure, and low antibody levels (hypogammaglobulinemia). Persistent low blood cell counts and loss of antibody-producing B cells also contributed to a weakened immune state. Risk was particularly high with BCMA-targeted therapies and continuous bispecific antibody administration.\u003c\/p\u003e\n\u003ch3\u003eWhat prevention strategies can reduce infections during these treatments?\u003c\/h3\u003e\n\u003cp\u003eThe review found that antiviral prophylaxis against HSV and VZV, PJP prophylaxis, and antibacterial and antifungal prophylaxis during neutropenia reduced infections. Immunoglobulin replacement also helped: in one analysis, grade 3\/4 infections at 6 months occurred in 5.3% of patients receiving IVIG versus a higher rate in those who did not. Some risk remained despite these measures.\u003c\/p\u003e\n\u003ch3\u003eCan extending the time between doses lower the risk of severe infections?\u003c\/h3\u003e\n\u003cp\u003eYes, the review found evidence that extended dosing intervals may reduce infections, particularly severe infections, while preserving treatment efficacy. In the MajesTEC-3 trial, the incidence of new severe infections declined after patients transitioned to monthly dosing and reinforced immunoglobulin replacement strategies. This suggests response-adapted treatment strategies may improve safety and outcomes.\u003c\/p\u003e\n\u003ch3\u003eAre infection rates different between CAR-T cell therapy and bispecific antibodies?\u003c\/h3\u003e\n\u003cp\u003eReal-world data suggest higher infection-related healthcare use and mortality with bispecific antibodies compared with CAR-T therapy, but direct head-to-head comparisons are lacking. For example, one real-world analysis found grade 3 or higher infection rates of 19% for CAR-T versus 76% for bispecific antibodies. These differences may reflect differences in patient populations and treatment settings.\u003c\/p\u003e\n\u003ch3\u003eWhen should a patient with multiple myeloma considering CAR-T cell therapy or bispecific antibodies seek a second opinion?\u003c\/h3\u003e\n\u003cp\u003eInfections occur in roughly 40–80% of patients receiving CAR-T cell therapy or bispecific antibodies, with grade 3 or higher infections exceeding 50% in several bispecific antibody studies. Risk is highest in the first 30 days after CAR-T infusion and during the first months of bispecific antibody therapy. Because prevention strategies such as antiviral and PJP prophylaxis, immunoglobulin replacement, and extended dosing intervals can reduce this risk, a second opinion can help confirm whether the recommended regimen and its supportive care plan are appropriate. Diagnostic Detectives Network provides independent expert second opinions.\u003c\/p\u003e\n\u003c!-- ddn:faq:end --\u003e\n\n\u003ch2 id=\"source\"\u003eSource Information\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eOriginal article title:\u003c\/strong\u003e Infectious toxicities associated with bispecific antibodies and CAR-T Cells in multiple myeloma: a systematic review.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eAuthors:\u003c\/strong\u003e Magdalena Benda, Patrick Reimann, Wolfgang Willenbacher, Eberhard Gunsilius, Katja Weisel, Irene Strassl, Maria Theresa Krauth, Stefan Knop, Thomas Winder, Normann Steiner\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003ePublication:\u003c\/strong\u003e Annals of Hematology (2026) 105:397\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eDOI:\u003c\/strong\u003e https:\/\/doi.org\/10.1007\/s00277-026-07140-8\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eReceived:\u003c\/strong\u003e 4 May 2026 \/ \u003cstrong\u003eAccepted:\u003c\/strong\u003e 15 June 2026 \/ \u003cstrong\u003ePublished online:\u003c\/strong\u003e 18 June 2026\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eAffiliated institutions:\u003c\/strong\u003e Department of Internal Medicine II, Feldkirch Academic Teaching Hospital, Feldkirch, Austria; Faculty of Medical Sciences, Private University of the Principality of Liechtenstein, Triesen, Principality of Liechtenstein; Molecular Biology Laboratory, Vorarlberg Institute for Vascular Investigation and Treatment, Dornbirn, Austria; Department of Internal Medicine V, Comprehensive Cancer Center Innsbruck, Medical University of Innsbruck, Innsbruck, Austria; Connect to Cure, Syndena GmbH, Innsbruck, Austria; Department of Oncology, Hematology and Bone Marrow Transplantation with Section Pneumology, University Cancer Center Hamburg-Eppendorf, Hamburg, Germany; Division of Hematology with Stem Cell Transplantation, Hemostaseology and Medical Oncology, Department of Internal Medicine I, Ordensklinikum Linz, Linz, Austria; Medical Faculty, Johannes Kepler University Linz, Linz, Austria; Department of Internal Medicine I, Division Hematology \u0026amp; Hemostaseology, Medical University of Vienna, Vienna, Austria; Department of Internal Medicine 5, Hematology and Oncology, Nuremberg General Hospital, Paracelsus Medical University, Nuremberg, Germany; University of Zurich, Zurich, Switzerland\u003c\/p\u003e\n\n\u003cp\u003e\u003cem\u003eThis patient-friendly article is based on peer-reviewed research.\u003c\/em\u003e\u003c\/p\u003e","brand":"DiagnosticDetectives.Com","offers":[{"title":"Default Title","offer_id":47807313969308,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0599\/5449\/5644\/files\/ddn-medical-article-infections-after-car-t-cell-therapy-and-bispecific-antibodies-in-multiple-myeloma-what-patients-need-to-know-hero.png?v=1792732902","url":"https:\/\/diagnosticdetectives.com\/ja\/products\/infections-after-car-t-cell-therapy-and-bispecific-antibodies-in-multiple-myeloma-what-patients-need-to-know","provider":"DiagnosticDetectives.Com","version":"1.0","type":"link"}