Minimal residual disease negativity by next-generation flow cytometry is associated with improved organ response in AL amyloidosis

Changing lanes: extending CAR T-cell therapy to high-risk plasma cell dyscrasias

Chimeric antigen receptor (CAR) cellular therapies have advanced outcomes in challenging hematologic malignancies like leukemia, lymphoma, and multiple myeloma. Plasma cell-directed CAR T-cell therapies have been particularly beneficial in multiple myeloma, suggesting that these agents may have a role in other challenging plasma cell disorders such as systemic AL amyloidosis and plasma cell leukemia. AL amyloidosis is a monoclonal plasma cell disorder resulting in the deposition of protein fibrils that compromise end-organ function. Delays in diagnosis can result in end-organ dysfunction and organ failure, making designing and completing treatment difficult. Plasma cell leukemia (PCL) is a rare and highly challenging malignancy with dismal survival outcomes despite aggressive therapy. Both diagnoses are currently treated with regimens borrowed from myeloma: a combination of novel agents and chemotherapy induction, then autologous stem cell transplantation (ASCT), with the current practice trending towards consolidation and maintenance. Unfortunately, only 20% of AL amyloidosis patients are transplant-eligible at diagnosis. Those transplant-ineligible (TIE) patients are treated with combination induction chemotherapy, which may be limited by worsening disease-related end-organ dysfunction. Plasma cell leukemia patients are still very likely to relapse after this intensive and prolonged therapy. Despite the promise of a shorter course of therapy, CAR T-cell therapies directed against plasma cells have not been rigorously investigated in patients with AL amyloidosis or PCL; most trials of MM have excluded these patients. Herein, we describe current treatment paradigms for AL amyloidosis and PCL and review the evidence for CAR T-cell therapies in these challenging plasma cell disorders. Further investigation into CAR T-cell therapies for plasma cell disorders other than multiple myeloma is warranted.

Between Charybdis and Scylla-an Odyssey in AL amyloidosis: insights and learnings from a narrative review and case report series

Being "between Scylla and Charybdis" is an idiom derived from Greek mythology to mean "between a rock and a hard place" and clinicians managing amyloid light-chain (AL) amyloidosis often find themselves in this predicament. AL amyloidosis is caused by monoclonal light chains, most commonly produced by CD-38 positive plasma cells in target organs. The disease usually involves significant cardiac and/or renal involvement, but the systemic nature of the disease often leads to variable and non-specific manifestations that can critically delay early diagnosis and treatment. Here, we present a case series reflecting primarily the cardiologist and hematologist perspective to uniquely illustrate key learnings that we believe have the potential to improve diagnosis timelines, treatment initiation, and ultimately improve outcomes for this severe disease. Through our case series, we illustrate that to achieve an accurate diagnosis, a high degree of clinical suspicion is needed, and we stress the important requirement of substantial multi-disciplinary collaboration. Our experience strongly indicates that AL amyloidosis patients presenting with cardiac symptoms need to be identified and treated rapidly, prior to the development of irreversible cardiotoxicity. In addition, patients without significant cardiac involvement may benefit from rapid initial treatment with daratumumab along with cyclophosphamide-bortezomib-dexamethasone, which can render patients eligible for autologous stem cell transplant (ASCT) or in some instances means they can forgo ASCT completely. Increased awareness of the disease is needed among general cardiologists and hematologists, and specialized centers with the relevant expertise should be willing to accept patients for fast-track evaluation as part of their standard procedures, due to the unique contribution they can offer in the clinical management of this life-threatening disease.

Light-chain (AL) amyloidosis for nephrologists-treatment standard

Amyloidosis is a group of complex diseases caused by the misfolding and aggregation of proteins into amyloid fibrils. Light-chain (AL) amyloidosis is one of the most prevalent forms of amyloidosis, characterized by the gradual proliferation of light chains from plasma cell clones. A growing body of evidence has contributed to our understanding of its pathogenesis, presentation and clinical course. Increased recognition of its clinical sequelae has increased the prevalence of AL amyloidosis. Renal involvement, seen in up to 70% of cases, is particularly challenging due to its impact on quality of life and access to treatment options. Thus, early recognition of its unique sequelae, appropriate staging and a comprehensive understanding of treatment options balanced by their organ toxicities are crucial to managing this disease. We review the current treatment standards and discuss novel developments in the pathophysiology, diagnosis, outcome prediction and management of AL amyloidosis for the Nephrologist.

Maintenance therapy promotes profound organ and haematologic response in light-chain amyloidosis patients not undergoing autologous stem cell transplantation

BACKGROUND

Evidence on maintenance therapy following frontline induction is sparse in primary light-chain amyloidosis (AL), especially for those who do not undergo autologous haematopoietic stem cell transplantation (ASCT).

METHODS

We enrolled primary AL patients who achieved at least haematologic very good partial response (VGPR) by the 4th month at the frontline from December 2008 to June 2023 at Zhongshan Hospital, Fudan University. Those who followed maintenance therapy were identified as the maintenance group (n = 44), whereas those entering the observational phase were classified as the observational group (n = 24).

RESULTS

After 7.2(interquartile range, 4.7-18.6) months of maintenance therapy, 9(20.5%), 14(31.8%) and 5 (11.4%) patients achieved improvement in haematologic, cardiac and renal response respectively. Five (11.4%) patients had minimal residual disease (MRD) response conversion from positive to negative based on maintenance therapy. In the observation group, none of the patients had haematologic response improvement, with 3(12.5%) and 1(4.2%) patient showing cardiac and renal response improvement during follow-up.

CONCLUSION

This study identified the clinical benefits of maintenance therapy in patients with AL who did not undergo ASCT in real-world practice.

Light-chain amyloidosis with concomitant symptomatic myeloma (CRAB-SLiM features): clinical characteristics, cytogenetic abnormalities, and outcomes

BACKGROUND

Patients with light-chain (AL) amyloidosis and concomitant multiple myeloma (MM) are known to have a worse prognosis, while the prognostic implication of cytogenetic abnormalities (CA) and optimal treatment schemes are not well-established. By comparing patients with MM or AL amyloidosis (AL) alone, this study aimed to evaluate the clinical characteristics, CA, and outcomes of patients with AL amyloidosis and concomitant symptomatic MM (MM-AL) and sought to provide evidence for their management.

METHODS

In total, 915 consecutive patients with newly diagnosed AL amyloidosis or MM were retrospectively analyzed. Patients were classified as MM-alone, MM-AL or AL-alone. The presence of symptomatic MM was based on the International Myeloma Working Group criteria, and the diagnosis of AL amyloidosis was confirmed by Congo-red-positive biopsy and immunoelectron microscopy.

RESULTS

Of 915 patients, 658, 106, and 151 were in the MM-alone group, MM-AL group, and AL-alone group, respectively. The three groups shared a similar incidence rate of CA, while the prevalence of t(11;14) was significantly higher in the AL-alone group than in the MM-AL and MM-alone group (40.7% vs. 25.7% vs. 16.6%, p < 0.001), and the prevalence of del13q, gain1q21 and high-risk CA (HRCA) decrease in turn in MM-alone, MM-AL and AL-alone group (del13q, 46.5% vs. 39.4% vs. 28.5%, p < 0.001; gain1q21, 52.6% vs. 45.2% vs. 27.3%, p < 0.001; HRCA, 27.5% vs. 16.0 vs. 7.3%, p < 0.001). The progression-free survival (PFS) and overall survival (OS) of MM-AL patients (median, 12.8, and 25.2 months) were significantly inferior to patients with MM-alone and AL-alone. No significant difference in PFS and OS was found between MM-AL patients with and without HRCA. When stratified by the type of plasma cell disease and status of t(11;14), patients with MM-AL and t(11;14) presented the worst OS (median, 8.2 months, p < 0.001). Regarding the management of MM-AL, extended cycles of induction therapy and the use of maintenance therapy contributed to a better prognosis.

CONCLUSIONS

There was an apparent discrepancy in the distribution and prognostic implication of CA among different plasma cell diseases. Patients with MM-AL had the worst clinical outcomes, requiring extended duration of induction therapy and maintenance therapy.

Autologous stem cell transplantation in AL amyloidosis: Muddy waters

Immunoglobulin light chain (AL) amyloidosis is a malignant plasma cell dyscrasia causing multi-organ morbidity. High dose melphalan and autologous stem cell transplantation (ASCT) is a preferred consolidation approach and is safe with improved patient selection criteria. With the advent of bortezomib and daratumumab based induction therapy, nearly all patients can achieve deep hematological responses but follow up for daratumumab based induction is short. Consequently, the traditional approach of induction followed by ASCT is called into question. Given the multi-organ involvement of AL, endpoints beyond depth of response and hematological progression free survival (PFS) are important. Major organ dysfunction PFS (MOD-PFS) adds to PFS and is a composite endpoint of PFS, renal and cardiac organ progression, and overall survival. It is currently unknown which consolidative approach (ASCT or non-ASCT) will generate improved outcomes across the MOD-PFS spectrum a question the recently opened S2213 trial will attempt to answer.

Early minimal residual disease eradication in light chain amyloidosis generates deeper and faster cardiac response

Minimal residual disease (MRD) is of growing interest in light chain (AL) amyloidosis and is associated with higher rates of cardiac response. A new graded cardiac response criteria has been proposed for better assessment of cardiac improvement. We evaluated MRD status in 63 patients with cardiac AL amyloidosis using next generation flow cytometry (sensitivity ≥ 1*10-5) within four cycles after treatment initiation and cardiac response kinetics. All patients were treated with first-line proteasome inhibitor (100%) and predominantly bortezomib (87.3%). The overall early MRD negative rates were 33.3%. Patients who achieved early MRD negativity were less likely to harbor t(11;14) (21.1% vs 57.5%, P = 0.009). The MRD negative rates amongst patients in hematologic complete response were 66.7% (14/21), and in very good partial response 29.2% (7/24). Early MRD negativity was associated with a higher likelihood of achieving ≥ cardiac partial response (≥ CarPR) (66.7% vs 38.1%, P = 0.032) and ≥ cardiac very good partial response (≥ CarVGPR) (38.1% vs 11.9%, P = 0.023) throughout first-line therapy. The cumulative incidence curve of achieving ≥ CarPR (P = 0.034) and ≥ CarVGPR (P = 0.026) showed significant difference between early MRD negative and positive group. After a median follow-up time of 27.2 months, the median progression free survival was longer in early MRD negative group (not reached vs 31.3 months, P = 0.033). Early MRD eradication in cardiac AL amyloidosis generated deeper and faster cardiac organ response.

Improving care for systemic light-chain amyloidosis patients: is a multidisciplinary approach best?

INTRODUCTION

Light chain (AL) amyloidosis is a rare and complex disease which can affect various systems of the body. In common with many rare and multisystemic diseases, the breadth of diagnostic, clinical, and supportive expertise required to care for such patients is best met by a multidisciplinary team.

AREAS COVERED

We outline different phases of the patients' journey, including diagnosis, staging, treatment, and response assessment, to highlight common clinical issues best resolved by a multidisciplinary approach.

EXPERT OPINION

To extend the benefit of multidisciplinary care to the majority of patients with AL amyloidosis, innovative healthcare models such as telehealth and multisite multidisciplinary team meetings need to be implemented. The need for a multidisciplinary approach where such a wide array of healthcare skills is required also highlights the shortcomings of our current diagnostic and monitoring assays. Better access to diagnostic and subtyping assays is necessary. The ability to characterize and measure the causative amyloidogenic light chain as well as imaging techniques to accurately diagnose and monitor response to therapy is also needed and is currently an area of research focus.

Successes in translation

Translational research is key in advancing the diagnosis and therapy of systemic amyloidoses. This paper summarises our presentations at the ISA Workshop on Translation in Systemic Amyloidoses held in Athens on September 25-26, 2023. The critical advances made by the pioneers in the field are reviewed, with particular attention to the discoveries and developments of utmost importance to our understanding of what amyloid is and how the substance affects functions. Examples of translational research regarding the mechanisms of cardiac damage in light chain amyloidosis, the role of biomarkers in improving our understanding of the biology of the disease and patients' management, and the molecular mechanisms involved in the cytotoxicity are described. Advances in basic research continue to open new therapeutic avenues.

Circulating tumor cells help differentiate benign ovarian lesions from cancer before surgery: A literature review and proof of concept study using flow cytometry with fluorescence imaging

Current tools are insufficient for distinguishing patients with ovarian cancer from those with benign ovarian lesions before extensive surgery. The present study utilized a readily accessible platform employing a negative selection strategy, followed by flow cytometry, to enumerate circulating tumor cells (CTCs) in patients with ovarian cancer. These counts were compared with those from patients with benign ovarian lesions. CTC counts at baseline, before and after anticancer therapy, and across various clinical scenarios involving ovarian lesions were assessed. A negative-selection protocol we proposed was applied to patients with suspected ovarian cancer and prospectively utilized in those subsequently confirmed to have malignancy. The protocol was implemented before anticancer therapy and at months 3, 6, 9 and 12 post-treatment. A cut-off value for CTC number at 4.75 cells/ml was established to distinguish ovarian malignancy from benign lesions, with an area under the curve of 0.900 (P<0.001). In patients with ovarian cancer, multivariate Cox regression analysis revealed that baseline CTC counts and the decline in CTCs within the first three months post-therapy were significant predictors of prolonged progression-free survival. Additionally, baseline CTC counts independently prognosticated overall survival. CTC counts obtained with the proposed platform, used in the present study, suggest that pre-operative CTC testing may be able to differentiate between malignant and benign tumors. Moreover, CTC counts may indicate oncologic outcomes in patients with ovarian cancer who have undergone cancer therapies.

Immune Therapies in AL Amyloidosis-A Glimpse to the Future

Light-chain (AL) amyloidosis is a rare plasma cell disorder characterized by the deposition of misfolded immunoglobulin light chains in target organs, leading to multi-organ dysfunction. Treatment approaches have historically mirrored but lagged behind those of multiple myeloma (MM). Recent advancements in MM immunotherapy are gradually being evaluated and adopted in AL amyloidosis. This review explores the current state of immunotherapeutic strategies in AL amyloidosis, including monoclonal antibodies, antibody-drug conjugates, bispecific antibodies, and chimeric antigen receptor T-cell therapy. We discuss the unique challenges and prospects of these therapies in AL amyloidosis, including the exposure of frail AL amyloidosis patients to immune-mediated toxicities such as cytokine release syndrome (CRS) and immune effector-cell-associated neurotoxicity syndrome (ICANS), as well as their efficacy in promoting rapid and deep hematologic responses. Furthermore, we highlight the need for international initiatives and compassionate programs to provide access to these promising therapies and address critical unmet needs in AL amyloidosis management. Finally, we discuss future directions, including optimizing treatment sequencing and mitigating toxicities, to improve outcomes for AL amyloidosis patients.

Minimal residual disease in systemic light chain amyloidosis: a systematic review and meta-analysis

PURPOSE

Minimal residual disease (MRD) is a validated prognostic factor in several hematological malignancies. However, its role in systemic light chain (AL) amyloidosis remains controversial, and this systematic review and meta-analysis aims to fill this gap.

METHODS

We searched for relevant studies on Pubmed, Embase, and Cochrane Controlled Register of Trials, nine studies involving 451 patients were included and meta-analyzed. This systematic review has been registered in PROSPERO (CRD42023494169).

RESULTS

Our study found that in the group of patients who achieved very good partial response (VGPR) or better, MRD negativity was correlated with higher cardiac and renal response rates [pooled risk ratio (RR) = 0.74 (95% CI 0.62-0.89), 0.74 (95% CI 0.64-0.87), respectively]. Patients with MRD positivity had a higher hematologic progression rate within two years after MRD detection [pooled RR = 10.31 (95% CI 2.02-52.68)]; and a higher risk of hematologic + organ progression in the first year [pooled RR = 12.57 (95% CI 1.73-91.04)]. Moreover, MRD negativity was correlated with a better progression-free survival (PFS) [pooled hazard ratio (HR) = 0.27 (95% CI 0.17-0.45)]; but it did not significantly improve the overall survival (OS) [pooled HR = 0.34 (95% CI 0.11-1.07)].

CONCLUSION

In AL amyloidosis, our study supports that MRD negativity correlates with higher cardiac or renal response rates and indicates a better PFS in the follow-up. However, the correlation between OS and the status of MRD is not significant.

Complete responses in AL amyloidosis are unequal: the impact of free light chain mass spectrometry in AL amyloidosis

ABSTRACT

Amyloidogenic serum free light chains (sFLCs) drive disease progression in AL amyloidosis. Matrix-assisted laser desorption/ionization time of flight mass spectrometry-based FLC assay (FLC-MS) has greater sensitivity than conventional sFLC assays allowing for the detection of serological residual disease. We report the utility of FLC-MS in a large series of patients with AL amyloidosis assessing the impact of FLC-MS negativity after treatment on overall survival (OS) and organ response rates. Serum samples were analyzed using FLC-MS at diagnosis and at 6 and 12 months after treatment. The impact of FLC-MS negativity over standard hematologic responses on survival and organ response was assessed. A total of 487 patients were included; 290 (59%) and 349 (71.5%) had cardiac and renal involvement, respectively. There was 100% concordance between the light chain (LC) fibril type and LC isotype identified by FLC-MS. At 6 and 12 months, 81 (16.6%) and 101 (20.7%) were FLC-MS negative. Of those achieving a conventional hematologic complete response (CR) at 6 and 12 months, 45 (27.7%) and 64 (39%) were FLC-MS negative. At 12 months, median OS for CR + FLC-MS negative was not reached vs 108 months in CR + FLC-MS positive (P = .024). At 12 months, 70% of patients with FLC-MS negativity (vs 50% FLC-MS positive) achieved a cardiac response (P = .015). In a multivariate analysis, FLC-MS negativity at 12 months was an independent predictor of better outcomes. FLC-MS can detect persistent monoclonal light chains in a significant proportion of patients in a conventional hematologic CR. FLC-MS assessment promises to be a new standard for response assessment in AL amyloidosis.

Successful autologous stem cell transplantation for light chain proximal tubulopathy with severe kidney injury

Light chain proximal tubulopathy (LCPT) is a rare type of monoclonal gammopathy of renal significance. Clinicians should consider LCPT in the differential diagnosis of patients with renal or proximal tubular dysfunction with monoclonal gammopathy. They should confirm diagnosis by renal biopsy and initiate chemotherapy before disease progression.

Cardiac and renal AL amyloidosis controlled by autologous stem cell transplantation for 17 years accompanying late onset atrial fibrillation and complete atrioventricular block

Amyloid light chain (AL) amyloidosis is a rare hematologic disease that may involve multiple organs. Amongst the organs, cardiac involvement causes the greatest concern as its treatment is challenging. Diastolic dysfunction rapidly progresses to decompensated heart failure, pulseless electrical activity, and atrial standstill due to electro-mechanical dissociation resulting in death. High-dose melphalan plus autologous stem cell transplantation (HDM-ASCT) is the most radical treatment but its risk is very high and thus only less than 20% of patients can receive this therapy under criteria that can suppress treatment-related mortality. In substantial proportion of patients, levels of M protein remain elevated, and organ response cannot be achieved. Moreover, relapse may occur, making prediction of treatment response and judgement of disease eradication very difficult. Herein we report a case of AL amyloidosis who was treated with HDM-ASCT, resulting in preserved cardiac function and resolution of proteinuria for more than 17 years after HDM-ASCT ensuing atrial fibrillation and complete atrioventricular block required management by catheter ablation and pacemaker implantation 10 years and 12 years after transplantation, respectively.

Anti-B Cell Maturation Antigen Chimeric Antigen Receptor T Cell Therapy for the Treatment of AL Amyloidosis and Concurrent Relapsed/Refractory Multiple Myeloma: Preliminary Efficacy and Safety

While immunotherapies, such as CAR T therapy and bi-specific antibodies, have revolutionized the treatment of multiple myeloma (MM), patients with AL amyloidosis have been excluded from trials with these agents due to concerns of underlying autonomic, cardiac, and renal dysfunction, leading to potentially fatal toxicities from these therapies. In this communication, we described the outcomes of two patients with AL amyloidosis and concurrent MM with underlying cardiac and/or renal dysfunction who underwent anti-BCMA CAR T cell therapy with ide-cel or cilta-cel, received cytokine release syndrome prophylaxis, and tolerated therapy well with manageable toxicities and achieved a MRD-negative state. We described the preliminary efficacy and safety of CAR T in patients with AL amyloidosis and highlighted the importance of patient selection and medical optimization of cardiac and renal function prior to CAR T.

The impact of Post-Transplant doxycycline in AL amyloidosis - updated results after Long-Term follow up

INTRODUCTION

The current treatment paradigm of AL amyloidosis lacks effective fibril-directed therapies. Doxycycline has been shown to have anti-fibril properties in preclinical models. In 2012, we reported that posttransplant prophylaxis with doxycycline was associated with improved survival compared to penicillin in patients with haematologic response. We provide here updated results after long-term follow up.

METHODS

We included 553 patients who underwent transplant between July 24th, 1996, and June 24th, 2014. Doxycycline 100 mg daily was used for prophylaxis in patients with penicillin allergy; since 2013, doxycycline was used as the standard for prophylaxis. Prophylaxis was typically continued for a year after transplant.

RESULTS

The median follow-up from transplant was 12.7 years. Doxycycline was used for prophylaxis in 33% of patients; the rest received penicillin. The median time to next treatment was 6.0 (95%CI; 4.4-8.8) years and 6.0 (95%CI; 4.9-7.1) years in the doxycycline and penicillin groups, respectively (p = .89). The median overall survival was 12.0 (95%CI: 11.0-19.6) years and 11.0 (95%CI: 9.6-12.7) years in the 2 groups, respectively (p = .17). There was a minimal trend towards improved survival with doxycycline among patients with ≥ very good partial response and among patients with organ response that was not statistically significant.

CONCLUSION

After long-term follow-up, there is no clear evidence to support benefit of doxycycline in the post-transplant setting.

Graded Cardiac Response Criteria for Patients With Systemic Light Chain Amyloidosis

PURPOSE

Binary cardiac response assessment using cardiac biomarkers is prognostic in light chain amyloidosis. Previous studies suggested four-level cardiac responses using N-terminal prohormone of brain natiuretic peptide improves prognostic prediction. This study was designed to validate graded cardiac response criteria using N-terminal prohormone of brain natiuretic peptide/brain natiuretic peptide.

PATIENTS AND METHODS

This retrospective, multicenter study included patients with light chain amyloidosis who achieved at least a hematologic partial response (PR) and were evaluable for cardiac response. Four response criteria were tested on the basis of natriuretic peptide response depth: cardiac complete response (CarCR), cardiac very good partial response (CarVGPR), cardiac PR (CarPR), and cardiac no response (CarNR). Response was classified as best response and at fixed time points (6, 12, and 24 months from therapy initiation). The study primary outcome was overall survival.

RESULTS

651 patients were included. Best CarCR, CarVGPR, CarPR, and CarNR were achieved in 16%, 26.4%, 22.9%, and 34.7% of patients, respectively. Patients in cardiac stage II were more likely to achieve CarCR than patients in cardiac stage IIIA and IIIB (22% v 13.5% v 3.2%; P < .001). A deeper cardiac response was associated with a longer survival (5-year overall survival 93%, 79%, 65%, and 33% for CarCR, CarVGPR, CarPR, and CarNR, respectively; P < .001). Fixed time-point analyses and time-varying covariates Cox regression analysis, to minimize survivorship bias, affirmed the independent survival advantage of deeper cardiac responses. Four-level response performed better than two-level response as early as 12 months from therapy initiation.

CONCLUSION

Graded cardiac response criteria allow better assessment of cardiac improvement compared with the traditional binary response system. The study re-emphasizes the importance of early diagnosis, which increases the likelihood of deep cardiac responses.

Guidelines for non-transplant chemotherapy for treatment of systemic AL amyloidosis: EHA-ISA working group

BACKGROUND

This guideline has been developed jointly by the European Society of Haematology and International Society of Amyloidosis recommending non-transplant chemotherapy treatment for patients with AL amyloidosis.

METHODS

A review of literature and grading of evidence as well as expert recommendations by the ESH and ISA guideline committees.

RESULTS AND CONCLUSIONS

The recommendations of this committee suggest that treatment follows the clinical presentation which determines treatment tolerance tempered by potential side effects to select and modify use of drugs in AL amyloidosis. All patients with AL amyloidosis should be considered for clinical trials where available. Daratumumab-VCD is recommended from most untreated patients (VCD or VMDex if daratumumab is unavailable). At relapse, the two guiding principles are the depth and duration of initial response, use of a class of agents not previously exposed as well as the limitation imposed by patients' fitness/frailty and end organ damage. Targeted agents like venetoclax need urgent prospective evaluation. Future prospective trials should include advanced stage patients to allow for evidence-based treatment decisions. Therapies targeting amyloid fibrils or those reducing the proteotoxicity of amyloidogenic light chains/oligomers are urgently needed.

Diagnosis and Treatment of AL Amyloidosis

Systemic light chain (AL) amyloidosis is caused by an usually small B cell clone that produces a toxic light chain forming amyloid deposits in tissue. The heart and kidney are the major organs affected, but all others, with the exception of the CNS, can be involved. The disease is rapidly progressive, and it is still diagnosed late. Screening programs in patients followed by hematologists for plasma cell dyscrasias should be considered. The diagnosis requires demonstration in a tissue biopsy of amyloid deposits formed by immunoglobulin light chains. The workup of patients with AL amyloidosis requires adequate technology and expertise, and patients should be referred to specialized centers whenever possible. Stagings are based on cardiac and renal biomarkers and guides the choice of treatment. The combination of daratumumab, cyclophosphamide, bortezomib and dexamethasone (dara-CyBorD) is the current standard of care. Autologous stem cell transplant is performed in eligible patients, especially those who do not attain a satisfactory response to dara-CyBorD. Passive immunotherapy targeting the amyloid deposits combined with chemo-/immune-therapy targeting the amyloid clone is currently being tested in controlled clinical trials. Response to therapy is assessed based on validated criteria. Profound hematologic response is the early goal of treatment and should be accompanied over time by deepening organ response. Many relapsed/refractory patients are also treated with daratumumab combination, but novel regimens will be needed to rescue daratumumab-exposed subjects. Immunomodulatory drugs are the current cornerstone of rescue therapy, while immunotherapy targeting B-cell maturation antigen and inhibitors of Bcl-2 are promising alternatives.

Immunoglobulin Light Chain Amyloidosis: Diagnosis and Risk Assessment

Immunoglobulin light chain (AL) amyloidosis is a clonal plasma cell disorder with multiple clinical presentations. The diagnosis of AL amyloidosis requires a high index of suspicion, making a delay in diagnosis common, which contributes to the high early mortality seen in this disease. Establishing the diagnosis of AL amyloidosis requires the demonstration of tissue deposition of amyloid fibrils. A bone marrow biopsy and fat pad aspirate performed concurrently have a high sensitivity for the diagnosis of AL amyloidosis and negate the need for organ biopsies in most patients. An accurate diagnosis requires amyloid typing via additional testing, including tissue mass spectrometry. Prognostication for AL amyloidosis is largely driven by the organs impacted. Cardiac involvement represents the single most important prognostic marker, and the existing staging systems are driven by cardiac biomarkers. Apart from organ involvement, plasma cell percentage on the bone marrow biopsy, specific fluorescence in situ hybridization findings, age at diagnosis, and performance status are important prognostic markers. This review elaborates on the diagnostic testing and prognostication for patients with newly diagnosed AL amyloidosis.

Bad players in AL amyloidosis in the current era of treatment

INTRODUCTION

Systemic AL amyloidosis (ALA) is a clonal plasma cell (PC) disease characterized by deposition of amyloid fibrils in different organs and tissues. Traditionally, the prognosis of ALA is poor and is primarily defined by cardiac involvement. The modern prognostic models are based on cardiac markers and free light chain difference (dFLC). Cardiac biomarkers have low specificity and are dependent on renal function, volume status, and cardiac diseases other than ALA. New therapies significantly improved the prognosis of the disease. The advancements in technologies - cardiac echocardiography (ECHO) and cardiac MRI (CMR), as well as new biological markers, relying on cardiac injury, inflammation, endothelial damage, and clonal and non-clonal PC markers are promising.

AREAS COVERED

An update on the prognostic significance of cardiac ALA, number of involved organs, response to treatment, including minimal residual disease (MRD), ECHO, MRI, and new biological markers will be discussed. The literature search was done in PubMed and Google Scholar, and the most recent and relevant data are included.

EXPERT OPINION

Prospective multicenter trials, evaluating multiple clinical and laboratory parameters, should be done to improve the risk assessment models in ALA in the modern era of therapy.

Individualized Approach to Management of Light Chain Amyloidosis

Systemic light chain (AL) amyloidosis is caused by a B-cell (most commonly plasma cell) clone that produces a toxic light chain that forms amyloid fibrils in tissues and causes severe, progressive organ dysfunction. The clinical presentation is protean, and patients are usually extremely frail, thus requiring careful adaptation of the treatment approach. However, the severity of organ involvement can be accurately assessed with biomarkers that allow a sharp prognostic stratification and precise tailoring of the treatment strategy. Moreover, the availability of biomarker-based response criteria also allows adjustment of the treatment approach over time. The recent completion of 3 large randomized clinical trials has offered new evidence for designing appropriate treatments. All this information has recently been integrated in the joint guidelines of the International Society of Amyloidosis and the European Hematology Association for the treatment of AL amyloidosis. Other clinical trials are underway testing new agents directed against the amyloid clone and the amyloid deposits. Our understanding of the peculiarities of the amyloid clone, as well as our ability to detect residual clonal disease and improve organ dysfunction, are also being refined and will result in more precise personalization of the treatment approach.

Feasibility of a Novel Academic BCMA-CART (HBI0101) for the Treatment of Relapsed and Refractory AL Amyloidosis

PURPOSE

AL amyloidosis (AL) treatments are generally based on those employed for multiple myeloma. Anti-B-cell maturation antigen (BCMA) chimeric antigen receptor T (CART)-cell therapy, already approved for multiple myeloma, might be too toxic for patients with AL.

EXPERIMENTAL DESIGN

Here we describe the ex vivo applicability of a novel in-house, academic anti-BCMA CAR construct on AL primary cells, as well as the safety and efficacy in 4 patients with relapsed/refractory (RR) primary AL, treated in a phase I clinical trial (NCT04720313).

RESULTS

Three had MAYO stage IIIa cardiac involvement at enrollment. The treatment proved relatively safe, with a short and manageable grade 3 cytokine release syndrome evident in 2 patients and no neurotoxicity in any. Cardiac decompensations, observed in 2 patients, were also short and manageable. The overall hematologic response and complete response rates were observed in all patients with an organ response evident in all four. Within a median follow-up period of 5.2 (2.5-9.5) months, all 4 patients maintained their responses.

CONCLUSIONS

BCMA-CART cells provide a first proof-of-concept that this therapy is safe enough and highly efficacious for the treatment of patients with advanced, RR AL.

Advances in the treatment of light chain amyloidosis

PURPOSE OF REVIEW

After many years, the management of systemic light chain (AL) amyloidosis is entering the era of evidence-based medicine, with three recently published randomized clinical trials, a regimen (daratumumab, cyclophosphamide, bortezomib, and dexamethasone, daratumumab-CyBorD) labeled for upfront therapy, more clinical trials ongoing, and published guidelines. In this review, we discuss how current practice is changing based on this data.

RECENT FINDINGS

Daratumumab-CyBorD grants unprecedentedly high rates of hematologic and organ response and became the novel standard-of-care in AL amyloidosis. The International Society of Amyloidosis and the European Hematology Association issued common guidelines for autologous stem cell transplant (ASCT) in this disease. Improved patient selection and effective induction regimens greatly reduced ASCT-related mortality. Venetoclax is emerging as a very effective option in patients harboring the common t(11;14) abnormality. Rapid and profound reduction of the amyloid free light chain can improve survival also at advanced stages.

SUMMARY

Daratumumab-CyBorD is being integrated into the treatment flow-chart whereas the role of ASCT is being redefined. New approaches are being tested in clinical trials. Treatment of daratumumab-refractory patients and validation of criteria of hematologic progression to be used in clinical trials and in individual patient management are current areas of research.

Recent guidelines for high dose chemotherapy and autologous stem cell transplant for systemic AL amyloidosis: a practitioner's perspective

INTRODUCTION

High dose melphalan followed by autologous stem cell transplant (ASCT) has been transformative in treating AL amyloidosis since the early nineties. Recently, the European Haematology Association (EHA) and International Society of Amyloidosis (ISA) have developed a combined guideline for the management of patients undergoing an ASCT for AL amyloidosis.

AREAS COVERED

In this practitioner's perspective, we review the guideline, focussing on 6 major areas and offer practical advice for its application. We provide a perspective on the optimal use of ASCT and its potential application in the future.

EXPERT OPINION

The EHA-ISA guideline comprehensively outlines the practicalities of performing an ASCT in AL amyloidosis. The critical aspect is careful patient selection. Vigilant fluid balance assessments are crucial as associated complications are common and dangerous.The role of ASCT is changing with improving haematological responses associated with novel agents. Evidence is limited for the use of ASCT in patients who achieve a complete haematological response (CR). Therefore, ASCT should be considered for those who only achieve a very good partial response (VGPR)/partial response (PR) and fulfil the strict selection criteria. Future research identifying the cohort who would benefit most from ASCT in the era of novel therapies is warranted.

A UK consensus algorithm for early treatment modification in newly diagnosed systemic light-chain amyloidosis

Depth of response is the critical determinant of prognosis in amyloid light-chain (AL) amyloidosis. Here, we aim to identify patients who are unlikely to improve response based on analysis of baseline characteristics and 1-month response. In a multivariate model, difference in involved amyloidogenic and uninvolved serum free light chains (dFLC) at diagnosis (dFLC >400 mg/l, odds ratio [OR] 4.051, p < 0.005) and no response at 1 month (OR 4.787, p < 0.005) were significant predictors of no improvement in response. Only 5% of patients with a dFLC of >400 mg/l and no response at 1 month improved their response (p < 0.005). We suggest that these patients should switch treatment early, subject to their functional status.

Light Chain Amyloidosis: Epidemiology, Staging, and Prognostication

Amyloidosis is a disorder of protein misfolding and metabolism in which insoluble fibrils are deposited in various tissues, causing organ dysfunction and eventually death. Out of the 60-plus heterogeneous amyloidogenic proteins that have been identified, approximately 30 are associated with human disease. The unifying feature of these proteins is their tendency to form beta-pleated sheets aligned in an antiparallel fashion. These sheets then form rigid, nonbranching fibrils that resist proteolysis, causing mechanical disruption and local oxidative stress in affected organs such as the heart, liver, kidneys, nervous system, and gastrointestinal tract. Here we review the epidemiology of light chain amyloidosis, the staging, and the concomitant prognostication that is critical in determining the appropriate treatment.

AL amyloidosis: untangling new therapies

Systemic light chain (AL) amyloidosis is a protein misfolding disorder characterized by the deposition of abnormal immunoglobulin light chains in fibrillary aggregates, resulting in end-organ damage. Several unique challenges face treating physicians, including delayed diagnosis, advanced vital organ involvement, and morbidity with treatment. Aggressive supportive care and risk-adapted application of plasma cell-directed therapies are the cornerstones of management. The therapeutic revolution in multiple myeloma will likely further expand the arsenal against plasma cells. Careful investigation of these agents will be critical to establish their role in this fragile population. The promise of fibril-directed therapies to restore organ function remains despite early disappointments. In this review, we discuss new therapies to tackle AL amyloidosis using a case-based approach.

AL Amyloidosis: Current Chemotherapy and Immune Therapy Treatment Strategies: JACC: CardioOncology State-of-the-Art Review

Immunoglobulin light chain (AL) amyloidosis is an incurable plasma cell disorder characterized by deposition of fibrils of misfolded immunoglobulin free light chains (FLC) in target organs, leading to failure. Cardiac involvement is common in AL amyloidosis and represents the single most adverse prognostic feature. A high index of clinical suspicion with rapid tissue diagnosis and commencement of combinatorial, highly effective cytoreductive therapy is crucial to arrest the process of amyloid deposition and preserve organ function. The clinical use of molecularly targeted drugs, such as proteasome inhibitors and immunomodulatory agents, monoclonal antibodies such as daratumumab, and risk-adjusted autologous stem cell transplant in eligible patients, has radically changed the natural history of AL amyloidosis. Here, we review the state-of-the-art treatment landscape in AL amyloidosis with an eye toward future therapeutic venues to impact the outcome of this devastating illness.

How I Treat AL Amyloidosis

The treatment of patients with systemic light chain (AL) amyloidosis is a challenge to hematologists. Despite its generally small size, the underlying clone causes a rapidly progressing, often devastating multiorgan dysfunction through the toxic light chains that form amyloid deposits. Clinical manifestations are deceitful and too often recognized at an irreversible stage. However, hematologists are in the unique position to diagnose AL amyloidosis at a pre-symptomatic stage checking biomarkers of amyloid organ involvement in patients with monoclonal gammopathies at higher risk to develop the disease. Adequate technology and expertise are needed for a prompt and correct diagnosis, particularly for ruling out non-AL amyloidoses that are now also treatable. Therapy should be carefully tailored based on severity of organ involvement and clonal characteristics, and early and continual monitoring of response is critical. Three recent randomized clinical trials moved AL amyloidosis to evidence-based era. Above all, the daratumumab-bortezomib combination is a new standard-of-care for newly diagnosed patients inducing rapid and deep responses that translate into high rates of organ response. The availability of new effective drugs allows to better personalize the therapy, reduce toxicity, and improve outcomes. Patients should be treated within clinical trials whenever possible.

Comprehensive Review of AL amyloidosis: some practical recommendations

Amyloid light chain (AL) amyloidosis is among the more common and more severe of the amyloidoses usually involving the slow proliferation of a bone-marrow-residing plasma cell (PC) clone and the secretion of unstable immunoglobulin-free light chains (FLC) that infiltrate peripheral tissues and result in detrimental end-organ damage. Disease presentation is rather vague, and the hallmark of treatment is early diagnosis before irreversible end-organ damage. Once diagnosed, treatment decision is transplant-driven whereby ~20% of patients are eligible for autologous stem cell transplantation (ASCT) with or without bortezomib-based induction. In the setting of ASCT-ineligibility, bortezomib plays a central role in upfront treatment with the recent addition of daratumumab to the current emerging standard of care. In general, management of AL amyloidosis is aimed at achieving deep, durable responses with very close monitoring for early detection of relapse/refractory disease. This article provides a comprehensive review of the management of patients with AL amyloidosis including goals of therapy, current treatment guidelines in the setting of both ASCT-eligibility and ineligibility, treatment response monitoring recommendations, toxicity management, and treatment of relapse/refractory disease.