FDA Approval Summary: Idecabtagene Vicleucel for Relapsed or Refractory Multiple Myeloma.

In March 2021, the FDA approved idecabtagene vicleucel, a chimeric antigen receptor T-cell therapy targeting the B-cell maturation antigen (BCMA), for adult patients with relapsed/refractory multiple myeloma (RRMM) after ≥4 lines of therapy including an immunomodulatory agent, a proteasome inhibitor, and an anti-CD38 mAb. Approval was based on overall response rate (ORR), complete response (CR) rate, and duration of response (DOR) in 100 adult patients with RRMM treated with idecabtagene vicleucel in a single-arm trial. Patients received a single infusion of idecabtagene vicleucel, preceded by lymphodepleting chemotherapy with cyclophosphamide and fludarabine. Of the 100 patients in the efficacy evaluable population, ORR was 72% [95% confidence interval (CI), 62-81] with stringent CR rate of 28% (95% CI, 19-38). After median follow-up of 10.7 months, median DOR was 11 months (95% CI, 10.3-11.4) in responders (partial response or better) and 19 months [95% CI, 11.4 months, not estimable (NE)] in patients who achieved stringent CR. Serious adverse reactions occurred in 67% of 127 patients evaluated for safety. Grade 3 or higher cytokine release syndrome and neurologic toxicities occurred in 9% and 4%, respectively, leading to a Risk Evaluation and Mitigation Strategy. Hemophagocytic lymphohistiocytosis/macrophage activation syndrome occurred in 4%, with two fatalities. Prolonged cytopenia requiring hematopoietic rescue occurred in 2% (3/127), with two fatalities.

Cross-study safety analysis of risk factors in CAR T cell clinical trials: An FDA database pilot project.

The Chimeric Antigen Receptor (CAR) T Cell Safety Database Project explored the use of cross-study safety data to identify risk factors associated with severe cytokine release syndrome (sCRS) and severe neurological toxicities (sNTX) after CAR T cell administration. Sponsors voluntarily submitted data for 1,926 subjects from 17 phases 1 and 2 studies (six acute lymphocytic leukemia [ALL], five non-Hodgkin's lymphoma [NHL], and six multiple myeloma [MM] studies). Subjects with ALL had a higher risk for developing sCRS and sNTX compared with subjects with NHL or MM. Subjects who received CAR T cells produced with gammaretrovirus vectors including CD28 sequences had higher rates of sNTX compared with subjects who received products produced with other vector designs included in the database. Use of cytokine-directed therapies and corticosteroids at lower toxicity grades were associated with lower rates of sCRS. Although this exploratory study was limited by unadjusted cross-study comparisons, it independently reproduced known risk factors for CAR T cell toxicity. Findings provide stakeholders in the CAR T cell clinical development community information on safety trends for consideration in early phase clinical trial design, as well as avenues for additional research.

FDA Approval Summary: Axicabtagene Ciloleucel for Relapsed or Refractory Large B-cell Lymphoma.

In October 2017, the FDA granted regular approval to axicabtagene ciloleucel, a CD19-directed chimeric antigen receptor (CAR) T-cell therapy, for treatment of adult patients with relapsed or refractory large B-cell lymphoma after two or more lines of systemic therapy. Efficacy was based on complete remission (CR) rate and duration of response (DOR) in 101 adult patients with relapsed or refractory large B-cell lymphoma (median 3 prior systemic regimens) treated on a single-arm trial. Patients received a single infusion of axicabtagene ciloleucel, preceded by lymphodepleting chemotherapy with cyclophosphamide and fludarabine. The objective response rate per independent review committee was 72% [95% confidence interval (CI), 62-81], with a CR rate of 51% (95% CI, 41-62). With a median follow-up of 7.9 months, the median DOR was not reached in patients achieving CR (95% CI, 8.1 months; not estimable, NE), whereas patients with partial remission had an estimated median DOR of 2.1 months (95% CI, 1.3-5.3). Among 108 patients evaluated for safety, serious adverse reactions occurred in 52%. Cytokine release syndrome and neurologic toxicities occurred in 94% and 87% of patients, respectively, leading to implementation of a risk evaluation and mitigation strategy.

FDA Approval Summary: Tisagenlecleucel for Treatment of Patients with Relapsed or Refractory B-cell Precursor Acute Lymphoblastic Leukemia.

Tisagenlecleucel (Kymriah; Novartis Pharmaceuticals) is a CD19-directed genetically modified autologous T-cell immunotherapy. On August 30, 2017, the FDA approved tisagenlecleucel for treatment of patients up to 25 years of age with B-cell precursor acute lymphoblastic leukemia (ALL) that is refractory in second or later relapse. Approval was based on the complete remission (CR) rate, durability of CR, and minimal residual disease (MRD) <0.01% in a cohort of 63 children and young adults with relapsed or refractory ALL treated on a single-arm trial (CCTL019B2202). Treatment consisted of fludarabine and cyclophosphamide followed 2 to 14 days later by a single dose of tisagenlecleucel. The CR rate was 63% (95% confidence interval, 50%-75%), and all CRs had MRD <0.01%. With a median follow-up of 4.8 months, the median duration of response was not reached. Cytokine release syndrome (79%) and neurologic events (65%) were serious toxicities reported in the trial. With implementation of a Risk Evaluation and Mitigation Strategy, the benefit-risk profile was considered acceptable for this patient population with such resistant ALL. A study of safety with 15 years of follow-up is required as a condition of the approval.See related commentary by Geyer, p. 1133.

Evaluation of optic neuritis following human papillomavirus vaccination.

To assess the relationship between human papillomavirus (HPV) vaccination and occurrence of optic neuritis (ON) and to evaluate a claims-based algorithm for identification of ON. Females of 9-26 year olds in the HealthCore's Integrated Research Database (HIRDSM) with and without claims evidence of HPV vaccination between 2007 and 2012 were included in this study. Potential ON cases were identified using the claims-based algorithm, positive predictive value (PPV) was determined using medical chart review. For the claims analysis, two study designs, a self-controlled temporal scan statistic and a retrospective matched cohort analysis, were used. ON was defined based on an algorithm developed using diagnosis and procedure codes from the medical claims. The PPV for ON cases using charts that had enough information for reviewers to make a determination was 62.5% (95% CI: 49.5%-74.3%). With the self-controlled temporal scan statistic, the primary analysis restricting on recommended vaccination schedule timing showed an increased risk of potential ON after second dose (RR = 3.39; p = 0.03), this finding was not confirmed for any of the additional analyses performed for individual or combined doses. With the cohort design, there was no increased risk of potential ON following vaccination in either individual or combined dose analyses. The risk of potential ON was higher among participants with a history of prior autoimmune diseases. In conclusion, identifying confirmed ON cases through administrative claims data proved challenging. The claims-based analysis in this study did not provide evidence for an association of ON with HPV vaccination.

Adult polyglucosan body disease associated with lewy bodies and tremor.

BACKGROUND: Adult polyglucosan body disease (PGBD) is rare and typically presents with upper and lower motor neuron involvement and neurogenic bladder. Extrapyramidal features are unusual in PGBD and are presumed secondary to widespread pathology that includes the basal ganglia. There are no prior reports of Lewy bodies in PGBD. OBJECTIVE: To report a unique finding of Lewy bodies in a patient with PGBD. REPORT OF A CASE A 46-year-old woman initially presented with a 4-year history of resting tremor. The tremor responded to levodopa therapy. Several months later, she developed upper and lower motor neuron involvement and other clinical features of PGBD. A sural nerve biopsy specimen revealed intra-axonal polyglucosan bodies that confirmed the clinical diagnosis. Bulbar and limb weakness progressed, and she developed dementia. She died 6 years after onset. At autopsy, extensive polyglucosan body formation was found in many regions of the central nervous system. In addition, numerous alpha-synuclein staining Lewy bodies were observed in the substantia nigra, accompanied by marked neuron depopulation. CONCLUSIONS: To our knowledge, this is the first report of adult PGBD associated with Lewy bodies and levodopa-responsive tremor. Although polyglucosan bodies were seen in substantia nigra, it is most likely that our patient had coexisting Parkinson disease.

Challenges in the identification of cobalamin-deficiency polyneuropathy.

BACKGROUND: Diagnosing cobalamin (Cbl) deficiency as a cause of polyneuropathy (PN) is problematic, as the frequency of both disorders increases with age, and serum Cbl levels can be difficult to interpret. OBJECTIVES: To identify unique clinical or laboratory features among PN patients with Cbl deficiency and to examine the role of testing of serum metabolite levels in the identification of Cbl deficiency. DESIGN: Cohort survey comparing patients with Cbl deficiency and cryptogenic PN identified during a 2-year period. Cobalamin deficiency was diagnosed using low serum Cbl levels or elevated serum methylmalonic acid or homocysteine levels. SETTING: Academic neuromuscular clinic. RESULTS: Of 324 PN patients, 27 were diagnosed as having Cbl deficiency. Twelve had Cbl levels within the normal range, but elevated serum metabolite levels. Compared with patients with cryptogenic sensory/sensorimotor PN, those with Cbl deficiency were more likely to have concomitant involvement of the upper and lower extremities and experience symptom onset in the hands and a sudden onset of symptoms (P<.005). These differences were seen regardless of whether Cbl deficiency was defined using low Cbl levels or elevated serum metabolite levels. Autoimmune pernicious anemia was identified in 6 (50%) of 12 Cbl-deficient patients with normal serum Cbl levels. The patients with PN and Cbl deficiency showed little objective improvement after parenteral replacement therapy; however, progression occurred less often in these patients compared with those with cryptogenic sensory/sensorimotor PN (P =.02). CONCLUSIONS: This study highlights the challenges of proving that Cbl deficiency is the cause for PN and identifies clinical features that suggest Cbl-deficiency PN. Testing of serum metabolite levels may identify Cbl deficiency in some patients with normal serum Cbl levels.

Blunted circadian variation in autonomic regulation of sinus node function in veterans with Gulf War syndrome.

PURPOSE: To test the hypothesis that subtle abnormalities of the autonomic nervous system underlie the chronic symptoms reported by many Gulf War veterans, such as chronic diarrhea, dizziness, fatigue, and sexual dysfunction. METHODS: Twenty-two ill Gulf War veterans and 19 age-, sex-, and education-matched control veterans underwent measurement of circadian rhythm of heart rate variability by 24-hour electrocardiography, ambulatory blood pressure recording, Valsalva ratio testing, sympathetic skin response evaluation, sweat imprint testing, and polysomnography. Investigators were blinded to case- or control-group status. RESULTS: High-frequency spectral power of heart rate variability increased normally 2.2-fold during sleep in controls but only 1.2-fold in ill veterans (P <0.0001). In ill veterans as compared with controls, it was lower at night (P = 0.0006), higher during the morning (P = 0.007), but no different during the rest of the day (P = 0.8). The mean heart rate of ill veterans also declined less at night (P = 0.0002), and their corrected QT intervals tended to be longer over the full 24 hours (P = 0.07), particularly at night (P = 0.03). Blunting of the nocturnal heart rate dip in ill veterans was confirmed by 24-hour automatic ambulatory blood pressure monitoring (P = 0.05) and polysomnography (P = 0.03). These differences remained significant after adjusting for potential confounders. Cases and controls were similar on measures of sympathetic adrenergic and sudomotor function, sleep architecture, respiratory function, and circadian variation in blood pressure and body temperature. CONCLUSION: Some symptoms of Gulf War syndrome may be due to subtle autonomic nervous system dysfunction.

Physician and plan effects on satisfaction of Medicaid managed care patients with their health care and providers.

As many Medicaid patients move into managed care, it is important that physicians competing to serve these patients understand the factors that lead to patient satisfaction. This study uses survey data from 7,313 Oregon Medicaid managed care patients to create a model describing how provider effects and health plan effects relate to patients' satisfaction with their medical care and provider. Path analysis was used to test the explanatory power and strength of relationships in the model. Perceived technical and interpersonal physician quality and health plan rating were most strongly linked with these patients' satisfaction with their care and provider.

Evaluation of Guillain-Barré Syndrome among recipients of influenza vaccine in 2000 and 2001.

BACKGROUND: The 1976-1977 swine influenza vaccine was associated with an elevated risk of Guillain-Barré Syndrome (GBS), especially within 6 weeks after vaccination. A 2004 IOM report concluded that evidence was inadequate to accept or reject a causal relationship between subsequent influenza vaccine formulations and GBS. Studies published after the IOM report have been limited by passively reported data or lack of validation of coded diagnoses. PURPOSE: To evaluate whether influenza vaccine is associated with GBS. METHODS: Controlled observational study using national data from the Medicare program, which ensures a predominantly elderly population. People included had a Medicare claim for influenza vaccination during September-December in 2000 or 2001. Medical records were reviewed to classify definite, probable, or possible GBS (or not a case) using a standardized case definition. In a risk interval design, the incidence rate of GBS during Weeks 0-6 after vaccination (exposed period) was compared to Weeks 9-14 after vaccination (comparison period). Data collection occurred during 2003-2007, and analysis was conducted during 2007-2009. RESULTS: Primary analysis included 22.2 million vaccinees, among whom 164 definite or probable GBS cases with onset during Weeks 0-6 or 9-14 were identified. The incidence rate ratio (IRR [95% CIs]) based on the GBS rate in the vaccine-exposed versus comparison periods, was 1.04 (0.76, 1.43) for combined years; 0.86 (0.52, 1.41) among people vaccinated in 2000; and 1.21 (0.79, 1.86) among people vaccinated in 2001. Secondary analysis additionally included 74 possible GBS cases; results were similar. CONCLUSIONS: Overall, the results do not support an association between influenza vaccine receipt and GBS among the elderly for the years studied (2000-2001 and 2001-2002 formulations).

An analysis of disease severity based on SMN2 copy number in adults with spinal muscular atrophy.

To evaluate the effect of SMN2 copy number on disease severity in spinal muscular atrophy (SMA), we stratified 45 adult SMA patients based on SMN2 copy number (3 vs. 4 copies). Patients with 3 copies had an earlier age of onset and lower spinal muscular atrophy functional rating scale (SMAFRS) scores and were more likely to be non-ambulatory. There was, however, no difference between the groups in quantitative muscle strength or pulmonary function testing. Functional scale may be a more discriminating outcome measure for SMA clinical trials.

The challenge of diagnosing ALS in patients with prior poliomyelitis.

Four patients with postpolio syndrome (PPS) developed ALS. Weakness and atrophy started from previously unaffected extremities but, contrary to PPS, spread to all muscles leading to death within 0.4 to 8 (mean 3.9) years. Upper motor neuron signs were absent in the atrophic limbs. Abundant spontaneous activity and group atrophy in newly affected muscles were prominent. ALS can rarely occur in the postpolio population starting de novo rather than as evolution of PPS.

Randomized, controlled trial of intravenous immunoglobulin in myasthenia gravis.

We initiated a randomized, double-blinded, placebo-controlled trial of intravenous immunoglobulin (IVIG) treatment in myasthenia gravis (MG). Patients received IVIG 2 gm/kg at induction and 1 gm/kg after 3 weeks vs. 5% albumin placebo. The primary efficacy measurement was the change in the quantitative MG Score (QMG) at day 42. Fifteen patients were enrolled (6 to IVIG; 9 to placebo) before the study was terminated because of insufficient IVIG inventories. At day 42, there was no significant difference in primary or secondary outcome measurements between the two groups. In a subsequent 6-week open-label study of IVIG, positive trends were observed.