Author: RR

XPOVIO® (selinexor): A Treatment Approved for Multiple Myeloma as Early as First Relapse

RR

Author: Cristina Gasparetto, MD
Sponsored by: Karyopharm Therapeutics, Inc.
Dr. Gasparetto is a paid consultant for Karyopharm Therapeutics, Inc. and has been compensated.

Multiple myeloma (MM) remains an incurable hematologic cancer due to the clonal nature of the disease.1 With each relapse, cancer cells undergo clonal evolution and acquire new mutations that render them resistant to certain treatments.1 Triplet therapies combining proteasome inhibitors (PIs), immunomodulatory drugs (IMiDs), and anti-CD38 monoclonal antibodies (CD38-mAbs) have improved patient outcomes and their use has steadily increased over the past decade.2,3 When patients relapse after exposure to daratumumab (a CD38-mAb), the prognosis becomes unfavorable; even if patients previously responded to PIs or IMiDs, median survival may not reach one year.3 A significant unmet need therefore remains for providing durable disease control for patients with MM.1

For patients with previously-treated MM, the National Comprehensive Cancer Network® (NCCN®) recommends a new triplet regimen should preferably include drugs or drug classes patients have not been exposed to, or not exposed to for at least 6 months.4 For patients with MM who are triple class exposed, a selective inhibitor of nuclear export (SINE) may be a potential treatment class to consider in early relapsed (1-3 prior therapies) MM.4 Once-weekly XPOVIO® (selinexor), is a first-in-class, oral SINE compound approved as early as first relapse in MM that reversibly inhibits exportin 1 (XPO1).5 This action leads to accumulation of tumor suppressor proteins in the nucleus and reductions in several oncoproteins, such as c-myc and cyclin D1, cell cycle arrest, and apoptosis of cancer cells.5 Oral, once weekly selinexor (XPOVIO®) in combination with bortezomib and dexamethasone (XVd) is recommended by the NCCN as a Category 1 therapeutic option in early relapsed (1 to 3 prior therapies) MM.4

The efficacy and safety of XPOVIO was assessed in a phase 3, randomized, open-label trial comparing XPOVIO (100 mg once weekly) in combination with bortezomib (1.3 mg/m2) and dexamethasone (20 mg) with Vd alone in patients exposed to one to three prior lines of therapy.6 Patient disease characteristics were well balanced in both treatment groups and the primary endpoint was progression-free survival (PFS).5,6 Patients in the XVd group demonstrated a median PFS of 13.9 months (95% CI: 11.73-NE) compared with 9.5 months (95% CI: 8.11-10.78) in the Vd group (HR 0.70 [95% CI: 0.53-0.93], P=0.0075).6 In patients treated with XVd, a greater median PFS was consistently observed in certain subgroups compared with patients treated with Vd (Figure 1).6,7 When comparing patients 65 years of age and older to younger patients, older patients had a higher incidence of discontinuation due to an adverse reaction (28% vs 13%) and a higher incidence of serious adverse reactions (56% vs 47%).5

XPOVIO-Combination-Demonstrated-Sustained-PFSFigure 1. Median PFS in the XVd and Vd treatment groups (primary endpoint) and in select patient subgroups in the XVd trial.

Oral, once-weekly XPOVIO dosage may be adjusted to help mitigate potential adverse reactions (ARs).5 The indicated starting dose of XPOVIO is 100 mg once weekly and the dose may be reduced to 80 mg, 60 mg, or 40 mg based on ARs.5 Dose reductions were permitted in the XVd trial to help mitigate ARs – 65% of patients in the XVd group had a dose reduction and the median dose of XPOVIO in that group was 80 mg once weekly.5,7 Patients in my clinical practice typically get reduced from 100 mg to 60 mg once weekly and experience minimal tolerability issues at 60 mg. In an exploratory post-hoc analysis of the XVd trial, efficacy was maintained with XPOVIO dose reductions (Figure 2).7

Efficacy-Maintained-Even-With-XPOVIO-Dose-ReductionFigure 2. Median PFS in XPOVIO dose-reduced patients in the XVd trial.

XVd was not associated with serious organ toxicities of the cardiac, pulmonary, renal, or hepatic systems.6,7 Warnings and precautions include life-threatening thrombocytopenia and neutropenia, gastrointestinal toxicities, severe life-threatening hyponatremia, serious infection, and life-threatening neurological toxicities.5 The most common adverse reactions (≥20% with a difference between arms of >5% compared to Vd) were fatigue, nausea, decreased appetite, diarrhea, peripheral neuropathy, upper respiratory tract infection, decreased weight, cataract, and vomiting (Figure 3).5 The XVd trial protocol required a prophylactic 5-HT3 antagonist to address nausea but allowed for other interventions as required.7 Nausea events were reported in 50% of patients, however, treatment-related nausea associated with XPOVIO diminished over time; 92% of nausea cases were resolved/resolving in the first month of treatment.7 Patients should be counseled on what to expect with XPOVIO therapy and monitored throughout treatment, with more frequent monitoring during the first three months of treatment.5

Figure 3. Adverse reactions reported in the XVd trial.

Below we consider 2 hypothetical patients where XPOVIO may be considered.

Patient A is a 66-year-old woman with relapsed/refractory MM. She was started on lenalidomide, bortezomib, and dexamethasone, and received autologous stem cell transplant (ASCT) followed by lenalidomide maintenance, which she did well on for 16 months. Upon relapsing, she was given daratumumab, pomalidomide with dexamethasone, and after 7 months, imaging confirmed that her MM progressed again. Given her DPd exposure, Patient A (RVd → ASCT → R → DPd) may be a candidate for a class switch to XVd.

Patient B is a 74-year-old man with a history of hypertension and was diagnosed with MM 2 years ago. Because of his hypertension, he was unable to start a PI due to risk of cardiotoxicity and he is ASCT ineligible. His healthcare provider started him on daratumumab, lenalidomide, and dexamethasone (DRd), but after 2 years, he has relapsed. A class switch to XPOVIO could be considered for Patient B as his second-line therapy.

Healthcare providers should consider patients’ individual clinical characteristics when making treatment decisions. Consider switching class with XPOVIO® (selinexor) for patients at relapse, including those who have been exposed to a CD38-mAb–based regimen.5 Based on the results of the XVd trial and considering the clonal nature of MM, switching patients to XPOVIO may be an option to consider.

INDICATIONS
XPOVIO® (selinexor) is a prescription medicine approved:
• in combination with bortezomib and dexamethasone to treat adult patients with multiple myeloma who have received at least one prior therapy.
• in combination with dexamethasone for the treatment of adult patients with relapsed or refractory multiple myeloma who have received at least four prior therapies and whose disease is refractory to at least two proteasome inhibitors, at least two immunomodulatory agents, and an anti‐CD38 monoclonal antibody.

IMPORTANT SAFETY INFORMATION

Thrombocytopenia: XPOVIO can cause life-threatening thrombocytopenia, potentially leading to hemorrhage. Thrombocytopenia was reported in patients with multiple myeloma.
Thrombocytopenia is the leading cause of dosage modifications. Monitor platelet counts at baseline and throughout treatment. Monitor more frequently during the first 3 months of treatment. Monitor patients for signs and symptoms of bleeding. Interrupt, reduce dose, or permanently discontinue based on severity of adverse reaction.

Neutropenia: XPOVIO can cause life-threatening neutropenia, potentially increasing the risk of infection.
Monitor more frequently during the first 3 months of treatment. Consider supportive measures, including antimicrobials and growth factors (e.g., G-CSF). Interrupt, reduce dose, or permanently discontinue based on severity of adverse reaction.

Gastrointestinal Toxicity: XPOVIO can cause severe gastrointestinal toxicities in patients.

Nausea/Vomiting/Diarrhea: Provide prophylactic antiemetics or treatment as needed.

Anorexia/Weight Loss: Monitor weight, nutritional status, and volume status at baseline and throughout treatment and provide nutritional support, fluids, and electrolyte repletion as clinically indicated.

Hyponatremia: XPOVIO can cause severe or life-threatening hyponatremia.
Monitor sodium level at baseline and throughout treatment.

Serious Infection: XPOVIO can cause serious and fatal infections. Atypical infections reported after taking XPOVIO include, but are not limited to, fungal pneumonia and herpesvirus infection.

Neurological Toxicity: XPOVIO can cause life-threatening neurological toxicities.
Coadministration of XPOVIO with other products that cause dizziness or mental status changes may increase the risk of neurological toxicity.
Advise patients to refrain from driving and engaging in hazardous occupations or activities until the neurological toxicity fully resolves. Institute fall precautions as appropriate.

Embryo-Fetal Toxicity: XPOVIO can cause fetal harm when administered to a pregnant woman.
Advise pregnant women of the potential risk to a fetus. Advise females of reproductive potential and males with a female partner of reproductive potential to use effective contraception during treatment with XPOVIO and for 1 week after the last dose.

Cataracts: New onset or exacerbation of cataract has occurred during treatment with XPOVIO. The incidence of new onset or worsening cataract requiring clinical intervention was reported.

ADVERSE REACTIONS

The most common adverse reactions (ARs) (≥20%) in patients with multiple myeloma who received XVd were fatigue, nausea, decreased appetite, diarrhea, peripheral neuropathy, upper respiratory tract infection, decreased weight, cataract, and vomiting.

Grade 3-4 laboratory abnormalities (≥10%) were thrombocytopenia, lymphopenia, hypophosphatemia, anemia, hyponatremia and neutropenia.

Fatal ARs occurred in 6% of patients within 30 days of last treatment. Serious ARs occurred in 52% of patients. Treatment discontinuation rate due to ARs was 19%. The most frequent ARs requiring permanent discontinuation in >2% of patients included fatigue, nausea, thrombocytopenia, decreased appetite, peripheral neuropathy and vomiting. Adverse reactions led to XPOVIO dose interruption in 83% of patients and dose reduction in 64% of patients.

USE IN SPECIFIC POPULATIONS

No overall difference in effectiveness of XPOVIO was observed in patients >65 years old when compared with younger patients. Patients ≥65 years old had a higher incidence of discontinuation due to an adverse reaction (AR) and a higher incidence of serious ARs than younger patients.

The effect of end-stage renal disease (CLCR <15 mL/min) or hemodialysis on XPOVIO pharmacokinetics is unknown.

Please see full Prescribing Information.
To report SUSPECTED ADVERSE REACTIONS, contact Karyopharm Therapeutics Inc. at 1-888-209-9326 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

© 2022 Karyopharm Therapeutics Inc. US-XPOV-10/22-00003

References
1. Mikkilineni L, Kochenderfer JN. CAR T cell therapies for patients with multiple myeloma. Nat Rev Clin Oncol. 2021;18(2):71-84. doi:10.1038/s41571-020-0427-6
2. Braunlin M, Belani R, Buchanan J, Wheeling T, Kim C. Trends in the multiple myeloma treatment landscape and survival: a U.S. analysis using 2011-2019 oncology clinic electronic health record data. Leuk Lymphoma. 2021;62(2):377-386. doi:10.1080/10428194.2020.1827253
3. Gandhi UH, Cornell RF, Lakshman A, et al. Outcomes of patients with multiple myeloma refractory to CD38-targeted monoclonal antibody therapy. Leukemia. 2019;33(9):2266-2275. doi:10.1038/s41375-019-0435-7
4. Referenced with permission from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®) for Multiple Myeloma V.5.2022. © National Comprehensive Cancer Network, Inc. 2022. All rights reserved. Accessed October 18, 2022. To view the most recent and complete version of the guideline, go online to NCCN.org. NCCN makes no warranties of any kind whatsoever regarding their content, use or application and disclaims any responsibility for their application or use in any way.
5. XPOVIO (selinexor) [prescribing information]. Karyopharm Therapeutics Inc. https://www.karyopharm.com/wp-content/uploads/2019/07/NDA-212306-SN-0071-Prescribing-Information-01July2019.pdf
6. Grosicki S, Simonova M, Spicka I, et al. Once-per-week selinexor, bortezomib, and dexamethasone versus twice-per-week bortezomib and dexamethasone in patients with multiple myeloma (BOSTON): a randomised, open-label, phase 3 trial. The Lancet. 2020;396(10262):1563-1573. doi:10.1016/S0140-6736(20)32292-3
7. Data on File. Karyopharm Therapeutics Inc. 2021. Published online 2021.

BRUKINSA® Superior to IMBRUVICA® in Relapsed/Refractory CLL/SLL

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SUMMARY: The American Cancer Society estimates that for 2022, about 20,160 new cases of Chronic Lymphocytic Leukemia (CLL) will be diagnosed in the US and 4410 patients will die of the disease. CLL accounts for about one-quarter of the new cases of leukemia. The average age of patients diagnosed with CLL is around 70 years, and is rarely seen in people under age 40, and is extremely rare in children.

Bruton’s Tyrosine Kinase (BTK) is a member of the Tec family of kinases, downstream of the B-cell receptor and is predominantly expressed in B-cells. It is a mediator of B-cell receptor signaling in normal and transformed B-cells. Ibrutinib (IMBRUVICA®) is an oral, irreversible inhibitor of BTK and inhibits cell proliferation and promotes programmed cell death (Apoptosis) by blocking B-cell activation and signaling. IMBRUVICA® demonstrated survival benefits when compared to chemoimmunotherapy both in previously untreated (RESONATE-2), as well as relapsed (RESONATE) CLL patients. However, toxicities leading to IMBRUVICA® discontinuation occurred in a significant number of patients, and Atrial Fibrillation was noted in 11-16% of patients and hypertension rates were between 20-26%.

Zanubrutinib (BRUKINSA®) is an irreversible, potent, next-generation, small molecule inhibitor of Bruton’s Tyrosine Kinase, designed to deliver targeted and sustained inhibition of the BTK protein by optimizing bioavailability, half-life, and selectivity, while minimizing off-target inhibition of TEC- and EGFR-family kinases. It has been hypothesized that the increased selectivity of BRUKINSA® may minimize toxicities, (such as those often associated with IMBRUVICA®) and improve efficacy outcomes. BRUKINSA® demonstrated promising efficacy among patients with CLL/SLL (Small Lymphocytic Lymphoma), in early phase trials.

ALPINE study is a randomized, global, Phase III trial in which BRUKINSA® was compared with IMBRUVICA® in previously treated patients with relapsed or refractory CLL or SLL. In this trial, a total of 652 patients were randomly assigned 1:1 to receive either BRUKINSA® 160 mg orally twice daily or IMBRUVICA® 420 mg orally once daily, until disease progression or unacceptable toxicity. Enrolled patients had at least one prior systemic therapy and were required to have measurable lymphadenopathy by CT scan or MRI. Exclusion criteria included current or past Richter’s transformation and prior treatment with BTK inhibitors. Approximately 20% of patients had a del(17p) and/or TP53 mutation and fewer than 15% of patients were on anticoagulants. The Primary end point of the trial was Overall Response Rate (ORR) assessed by investigator and Independent Review Committee (IRC), and Secondary end points included Progression Free Survival (PFS), event rate of Atrial Fibrillation or Flutter, Duration of Response, Time to Treatment Failure, Overall Survival (OS), Patient-Reported Outcomes, and Safety.

BeiGene recently announced that BRUKINSA® achieved superior Progression Free Survival (PFS) when compared to IMBRUVICA® in the final analysis of this Phase III ALPINE trial, as assessed by an Independent Review Committee (IRC) and investigator. This data will be presented at future scientific meetings. The interim analysis conducted at a median follow-up was 15 months showed significantly higher Overall Response Rate with BRUKINSA®, compared with IMBRUVICA® (78.3% versus 62.5%; P =0.0006). The Overall Response Rate was higher in patients with del11q (83.6% versus 69.1%) and del17p (83.3% versus 53.8%) with BRUKINSA®, as well as the overall 12-month Progression Free Survival (94.9% versus 84.0%) and Overall Survival rates (97.0% versus 92.7%). Major bleeding rates as well as adverse events leading to treatment discontinuation, was lower with BRUKINSA®, compared to IMBRUVICA®. The rate of Atrial Fibrillation/Flutter, a pre-specified safety endpoint, was significantly lower with BRUKINSA®, compared to IMBRUVICA® (2.5% versus 10.1%; P=0.0014).

It was concluded from this randomized, Phase III study that, among patients with relapsed/refractory CLL/SLL, BRUKINSA® was superior to IMBRUVICA®, with a lower rate of Atrial Fibrillation/Flutter. The researchers added that BTK inhibition, with more complete and sustained BTK occupancy, results in improved efficacy and safety outcomes.

First interim analysis of ALPINE study: results of a phase 3 randomized study of zanubrutinib vs ibrutinib in patients with relapsed/refractory chronic lymphocytic leukemia/small lymphocytic lymphoma. Brown JR, Hillmen P, Eichhorst B, et al. Presented at: 2022 SOHO Annual Meeting; September 28-October 1, 2022; Houston, TX. Poster CLL-115.

RNF43 Mutations Predict Response to Anti-BRAF/EGFR Combination Therapy in BRAF V600E Metastatic Colorectal Cancer

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SUMMARY: ColoRectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 151,030 new cases of CRC will be diagnosed in the United States in 2022 and about 52,580 patients are expected to die of the disease. The lifetime risk of developing CRC is about 1 in 23.

Approximately 15-25% of the patients with CRC present with metastatic disease at the time of diagnosis (synchronous metastases) and 50-60% of the patients with CRC will develop metastatic disease during the course of their illness. Advanced colon cancer is often incurable and standard chemotherapy when combined with anti EGFR (Epidermal Growth Factor Receptor) targeted monoclonal antibodies such as VECTIBIX® (Panitumumab) and ERBITUX® (Cetuximab) as well as anti VEGF agent AVASTIN® (Bevacizumab), have demonstrated improvement in Progression Free Survival (PFS) and Overall Survival (OS). The benefit with anti EGFR agents however is only demonstrable in patients with metastatic CRC (mCRC) whose tumors do not harbor KRAS mutations in codons 12 and 13 of exon 2 (KRAS Wild Type). It is now also clear that even among the KRAS Wild Type patient group about 15-20% have other rare mutations such as NRAS and BRAF mutations, which confer resistance to anti EGFR agents. Patients with Stage IV CRC are now routinely analyzed for extended RAS and BRAF mutations. KRAS mutations are predictive of resistance to EGFR targeted therapy.

Approximately 8-15% of all metastatic CRC tumors present with BRAF V600E mutations, which is recognized as a marker of poor prognosis in this patient group. These patients predominantly present with right-sided proximal tumors, tend to have aggressive disease with a higher rate of peritoneal metastasis, and do not respond well to standard treatment intervention. Approximately 30% of the BRAF-mutated population in the metastatic setting has MSI-High tumors, but MSI-High status does not confer protection to this patient group. Further, in striking contrast to patients with melanoma harboring BRAF V600E mutations in whom there is a 70% Objective Response Rate with BRAF inhibitor monotherapy, there is little or no clinical benefit with the same treatment among BRAF V600E mutant CRC patients.

Preclinical studies have shown that inhibiting BRAF in colorectal tumors can transiently reduce Mitogen-Activated Protein (MAP) kinase signaling. However, this can result in feedback upregulation of EGFR signaling pathway, which can then reactivate the MAP kinase pathway. This aberrant signaling can be blocked by dual inhibition of both BRAF and EGFR. In the Phase III BEACON Colorectal Cancer study, a combination of BRAF inhibitor BRAFTOVI® (Encorafenib) and EGFR antagonist ERBITUX® (Cetuximab), with or without concomitant MEK inhibition improved Response Rates, Overall Survival and Progression Free Survival in patients with metastatic CRC with a BRAF V600E mutation. The FDA approved this doublet therapy in 2020 for this patient group. Despite this improved efficacy, a significant percentage of patients do not respond this therapy and among those who respond, the responses noted in CRC are still not as robust as has been in BRAF-mutant metastatic melanomas treated with anti-BRAF therapy. This suggests that there may be other factors modulating treatment response, including molecular determinants, that need to be identified, to optimize clinical management of these patients.

BRAF V600E mutated tumors in CRC are also associated with specific molecular features, including a low frequency of APC mutations and a high rate of mutations in the tumor suppressor gene RNF43 (Ring Finger Protein 43). RNF43 is a E3 ubiquitin ligase which negatively regulates Wnt signaling by inducing degradation of the Wnt receptors. It has been postulated that the a cross-talk between the MAPK and WNT signaling pathways may modulate the antitumor activity of anti-BRAF/EGFR therapy.

The researchers in this study sought to explore which genes were enriched for somatic mutations in responder and non-responder groups, among patients with BRAF V600E mutant CRC, treated with anti-BRAF/EGFR combination therapy. This study included 166 patients (N=166) with BRAF V600E mutant CRC of whom 98 patients received treatment with anti-BRAF/EGFR combination therapy (N=46 in the Discovery cohort and N=52 in the Validation cohort). The Control cohort (N=68) consisted of BRAF V600E mutant CRC patients treated with chemotherapy with or without antiangiogenic therapy, and were not exposed to anti-BRAF therapy. Whole-Exome Sequencing (WES) and/or targeted gene sequencing was performed on baseline tumor and/or plasma cell-free DNA (cfDNA) samples of all included patients, and over 20,000 genes were analyzed.

It was noted that RNF43 mutations were identified in 29% of BRAF V600E-mutated MicroSatellite-Stable (MSS) metastatic CRC tumors, and this finding was strongly associated with a clinical response to anti-BRAF/EGFR-based combination therapy. When compared to BRAF V600E-mutated, MicroSatellite-Stable metastatic CRC patients without the RNF43 mutation (RNF43 wild-type), patients with BRAF V600E-mutated, MicroSatellite-Stable metastatic CRC carrying a RNF43 mutation had a Response Rate of 72.7% versus 30.8% (P=0.03), longer median Progression Free Survival (10.1 months versus 4.1 months, HR=0.30; P=0.01) and longer median Overall Survival (13.6 months versus 7 months, HR=0.26; P=0.008). Conversely, the predictive value of RNF43 mutations seen in MicroSatellite-Stable tumors was not observed in MicroSatellite Instability (MSI)-High tumors.

The researchers concluded that these findings suggest that RNF43 may be a potential stratification biomarker that could help with decision making, in patients with MicroSatellite-Stable, BRAF V600E–mutant metastatic Colorectal cancer. They added that RNF43 gene may be a predictive biomarker of a response to treatment with anti-BRAF/EGFR combination therapy in this patient group.

RNF43 mutations predict response to anti-BRAF/EGFR combinatory therapies in BRAF V600E metastatic colorectal cancer. Elez, E, Ros J, Fernandez J, et al. Nature Medicine 2022;28:2162–2170.

FDA Approves TECVAYLI® for Relapsed or Refractory Multiple Myeloma

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SUMMARY: The FDA on October 25, 2022, granted accelerated approval to TECVAYLI® (Teclistamab-cqyv), the first bispecific B-Cell Maturation Antigen (BCMA)-directed CD3 T-cell engager, for adult patients with Relapsed or Refractory multiple myeloma who have received at least four prior lines of therapy, including a Proteasome Inhibitor, an Immunomodulatory agent, and an anti-CD38 monoclonal antibody. Multiple Myeloma is a clonal disorder of plasma cells in the bone marrow and the American Cancer Society estimates that in the United States, 34,470 new cases will be diagnosed in 2022 and 12,640 patients will die of the disease. Multiple Myeloma is a disease of the elderly, with a median age at diagnosis of 69 years and characterized by intrinsic clonal heterogeneity. Almost all patients eventually will relapse, and patients with a high-risk cytogenetic profile, extramedullary disease or refractory disease have the worst outcomes. The introduction of Proteasome Inhibitors, Immunomodulatory agents and CD 38 targeted therapies has resulted in higher Response Rates, as well as longer Progression Free Survival (PFS) and Overall Survival (OS), with the median survival for patients with myeloma approaching 10 years or more. Nonetheless, multiple myeloma in 2022 remains an incurable disease.

B-Cell Maturation Antigen (BCMA) is a member of the Tumor Necrosis Factor superfamily of proteins. It is a transmembrane signaling protein primarily expressed by malignant and normal plasma cells and some mature B cells. BCMA is involved in JNK and NF-kB signaling pathways that induce B-cell development and autoimmune responses. BCMA has been implicated in autoimmune disorders, as well as B-lymphocyte malignancies, Leukemia, Lymphomas, and Multiple Myeloma. At the time of writing, there are three BCMA-targeted therapies approved by the FDAfor patients with Relapsed or Refractory multiple myeloma with triple-class exposure. They include CARVYKTI® (Ciltacabtageneautoleucel) and ABECMA® (Idecabtagenevicleucel),which are B-Cell Maturation Antigen (BCMA)-directed genetically modified autologous T cell immunotherapies (CART-Cell therapies), and BLENREP® (Belantamabmafodotin-blmf), which is a B-Cell Maturation Antigen (BCMA)-directed antibody and microtubule inhibitor drug conjugate (Antibody Drug Conjugate). Even though CAR T-cell therapies have resulted in remarkable clinical responses, logistic challenges include at least 2 weeks of hospital stay, long manufacturing times, need for bridging therapy, and high cost of treatment.

TECVAYLI® is a bispecific antibody with dual binding sites, that targets both CD3 expressed on the surface of T cells and BCMA expressed on the surface of myeloma cells, and thereby mediates T-cell activation and lysis of BCMA-expressing myeloma cells. This effect occurs regardless of T-cell–receptor specificity or Major Histocompatibility Complex class I molecules on the surface of myeloma cells. This mechanism of action of TECVAYLI® is distinct from that of other available therapies for this patient group.

The present FDA approval was based on the efficacy and safety results from the pivotal, single-arm, multi-cohort, open-label, multi-center Phase 1/2 portion of MajesTEC-1 study, which enrolled 165 patients, who had Relapsed or Refractory myeloma after at least three therapy lines, including triple-class exposure to an Immunomodulatory drug, a Proteasome Inhibitor, and an anti-CD38 antibody. Patients received TECVAYLI® 1.5 mg/kg subcutaneously once weekly, after receiving step-up doses of 0.06 and 0.3 mg/kg separated by 2- 4 days and completed 2-4 days before the administration of the first full TECVAYLI® dose. Patients were hospitalized and premedicated with Dexamethasone, Acetaminophen, and Diphenhydramine for each step-up dose and for the first full dose of TECVAYLI®. Treatment was continued until disease progression, unacceptable toxicity, or the end of the study. The median age was 64 years, the median time between diagnosis and the first treatment dose was 6 years, 26% had at least one high-risk cytogenetic abnormality defined as del(17p), t(4;14), or t(14;16) among those with available cytogenetic data (N=148), 77.6% had triple-class refractory disease, and patients had received a median of 5 previous lines of therapy. The Primary end point was the Overall Response Rate (ORR), which was defined as a Partial Response or better according to the International Myeloma Working Group criteria, as assessed by an Independent Review Committee. Secondary end points included Duration of Response, Very Good Partial Response (VGPR) or better, Progression Free and Overall Survival, Minimal Residual Disease (MRD) status and Safety.

At a median follow-up of 14.1 months, the Overall Response Rate was 63%, with 39.4% having a Complete Response or better. Close to 60% of patients had a Very Good Partial Response or better. Approximately, 27% of patients had negative results for Minimal Residual Disease in bone marrow (<1 myeloma cell in 100,000 cells), and the MRD-negativity rate among the patients with a Complete Response or better was 46%. The median Duration of Response was 18.4 months, and the median duration of Progression Free Survival was 11.3 months. Common adverse events included Cytokine Release Syndrome (CRS) noted in 72% and were mostly Grade 1 or 2 and fully resolved. None of the patients discontinued TECVAYLI® due to CRS. Other common adverse events included neutropenia, anemia, and thrombocytopenia, as well as immune effector cell–associated neurotoxicity syndrome, but none of the patients discontinued therapy because of neurotoxic events.

It was concluded from this study that TECVAYLI® had substantial clinical activity, with a high rate of deep and durable response in patients with triple-class-exposed Relapsed or Refractory multiple myeloma. Toxic effects were common but were mainly of low grade and reversible. The researchers added that the efficacy of TECVAYLI® compared favorably with other FDA approved treatments that are currently available for later lines in multiple myeloma, including BLENREP® (Belantamabmafodotin-blmf), XPOVIO® (Selinexor), and CAR T-cell therapies.

Teclistamab in Relapsed or Refractory Multiple Myeloma. Moreau P, Garfall AL,van de DonkNW,et al. N Engl J Med 2022; 387:495-505

FDA Approves IMJUDO® plus IMFINZI® for Patients with Advanced Hepatocellular Carcinoma

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SUMMARY: The FDA on October 21, 2022, approved IMJUDO® (Tremelimumab) in combination with IMFINZI® (Durvalumab), for adult patients with unresectable HepatoCellular Carcinoma (HCC). The American Cancer Society estimates that for 2022, about 41,260 new cases of primary liver cancer and intrahepatic bile duct cancer will be diagnosed in the US and 30,520 patients will die of their disease. Liver cancer is seen more often in men than in women and the incidence has more than tripled since 1980. This increase has been attributed to the higher rate of Hepatitis C Virus (HCV) infection among baby boomers (born between 1945 through 1965). Obesity and Type II diabetes have also likely contributed to the increasing trend. Other risk factors include alcohol, which increases liver cancer risk by about 10% per drink per day, and tobacco use, which increases liver cancer risk by approximately 50%. HepatoCellular Carcinoma (HCC) is also a leading cause of cancer deaths worldwide, accounting for more than 700,000 deaths each year, and majority of patients typically present at an advanced stage. The prognosis for unresectable HCC remains poor and one year survival rate is less than 50% following diagnosis and only 7% of patients with advanced disease survive five years. NEXAVAR® was approved by the FDA in 2007 for the first line treatment of unresectable HepatoCellular Carcinoma (HCC) and the median Overall Survival was 10.7 months in the NEXAVAR® group and 7.9 months in the placebo group.

Immune checkpoints are cell surface inhibitory proteins/receptors that are expressed on activated T cells. They harness the immune system and prevent uncontrolled immune reactions by switching off the T cells of the immune system. Immune checkpoint proteins/receptors include CTLA-4 (Cytotoxic T-Lymphocyte Antigen 4, also known as CD152) and PD-1(Programmed cell Death 1). Checkpoint inhibitors unleash the T cells resulting in T cell proliferation, activation, and a therapeutic response.

IMFINZI® (Durvalumab) is a human monoclonal antibody that binds to the PD-L1 protein and blocks the interaction of PD-L1 with the PD-1 and CD80 proteins, countering the tumor’s immune-evading tactics and unleashes the T cells. IMJUDO® is a human monoclonal antibody that targets and blocks the activity of CTLA-4, contributing to T-cell activation, priming the immune response to cancer and fostering cancer cell death. In a Phase II study, a single priming dose of IMJUDO® added to IMFINZI® (STRIDE regimen), showed encouraging clinical activity and limited toxicity in patients with unresectable HepatoCellular Carcinoma (HCC), suggesting that a single exposure to IMJUDO® may be sufficient to improve upon activity of IMFINZI®.

HIMALAYA trial is a randomized, open-label, multicenter, global, Phase III study conducted in 190 centres across 16 countries, including in the US, Canada, Europe, South America and Asia. In this study, 1,171 patients with Stage III or IV unresectable HepatoCellular Carcinoma who had received no prior systemic therapy and were not eligible for locoregional therapy (treatment localized to the liver and surrounding tissue), were randomly assigned to receive either the STRIDE regimen which consisted of a single priming dose of IMJUDO® 300 mg IV added to IMFINZI® (Durvalumab) 1500 mg IV, followed IMFINZI® 1500 mg IV by every 4 weeks (N= 393), IMFINZI® monotherapy given at the same dose and schedule (N = 389) or NEXAVAR® (Sorafenib) 400 mg orally BID (N=389). Enrolled patients had ECOG performance status of 0 or 1 and Child-Pugh A disease and could not have main portal vein thrombosis. Patients were stratified based on macrovascular invasion (Yes versus No), etiology of liver disease (Hepatitis B virus versus Hepatitis C virus versus others), and ECOG Performance Status (0 versus 1). The Primary endpoint was Overall Survival (OS) for STRIDE regimen versus NEXAVAR® and key Secondary endpoints included OS for IMFINZI® monotherapy versus NEXAVAR®, Objective Response Rate and Progression Free Survival (PFS) for STRIDE and IMFINZI® monotherapy. The present FDA approval was based on a comparison of the 782 patients randomized to IMJUDO® plus IMFINZI® (STRIDE regimen) to NEXAVAR®.

The Primary objective of this study was met at the time of data cutoff. At a median follow up of 16.1 months of treatment with the STRIDE regimen, there was a 22% reduction in the risk of death for patients who received the STRIDE regimen compared to NEXAVAR® alone (HR=0.78; P=0.0035). The median OS with the STRIDE regimen was 16.4 months, compared with 13.8 months with NEXAVAR®, and the 3 year OS rate was 30.7% versus 20.2 % respectively. The Overall Response Rate for the combination STRIDE regimen was 20.1% compared to 5.1% for NEXAVAR®.

IMFINZI® monotherapy met the objective of OS non-Inferiority to NEXAVAR® (HR=0.86), and the median OS after 16.5 months of median follow up was 16.6 months with IMFINZI® monotherapy versus 13.8 months with NEXAVAR®, and the 3 year OS rate was 24.7% versus 20.2 % respectively. The Overall Response Rate with IMFINZI® monotherapy was 17% compared to 5.1% for NEXAVAR®. The Secondary endpoint of PFS was not superior in either investigational study group relative to the NEXAVAR® control arm. The most common adverse reactions occurring in patients were rash, diarrhea, fatigue, pruritis, musculoskeletal pain and abdominal pain.

It was concluded that HIMALAYA is the first large Phase III trial to add a novel single priming dose of an anti-CTLA4 antibody IMJUDO®, to another checkpoint inhibitor, IMFINZI®. This combination regimen (STRIDE) demonstrated superior efficacy and a favorable benefit-risk profile when compared with NEXAVAR® and should be considered a novel , first-line standard of care systemic therapy, for patients with unresectable Hepatocellular Carcinoma.

Tremelimumab plus Durvalumab in Unresectable Hepatocellular Carcinoma. Abou-Alfa GK, Lau G, Kudo M, et al. Published June 6, 2022. NEJM Evid 2022; 1 (8) DOI:https://doi.org/10.1056/EVIDoa2100070.

Improved Outcomes with Early Switch to Fulvestrant Plus Palbociclib in ESR1 Mutated Advanced Breast Cancer

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SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women (12%) will develop invasive breast cancer during their lifetime. Approximately 290,560 new cases of breast cancer will be diagnosed in 2022 and about 43,780 individuals will die of the disease, largely due to metastatic recurrence. Approximately 70% of breast tumors express Estrogen Receptors and/or Progesterone Receptors. The most common subtype of metastatic breast cancer is Hormone Receptor-positive (HR-positive), HER2-negative breast cancer (65% of all metastatic breast tumors), and these patients are often treated with anti-estrogen therapy as first line treatment. However, resistance to hormonal therapy occurs in most of the patients, with a median Overall Survival (OS) of 36 months. With the development of Cyclin Dependent Kinases (CDK) 4/6 inhibitors, endocrine therapy plus a CDK4/6 inhibitor is the mainstay for the management of ER+/HER2- metastatic breast cancer as first-line therapy. Even with this therapeutic combination, most patients will eventually experience disease progression, including development of ESR1 (Estrogen Receptor gene alpha) mutations.

ESR1 is the most common acquired mutation noted in breast tumors as they progress from primary to metastatic setting. These mutations promote ligand independent Estrogen Receptor activation and have been shown to promote resistance to estrogen deprivation therapy. It appears that ESR1 mutations are harbored in metastatic ER+ breast cancers with prior Aromatase Inhibitor (AI) therapy, but not in primary breast cancers, suggesting that ESR1 mutations may be selected by prior therapy with an AI, in advanced breast cancer. In a recently published study (JAMA Oncol.2016;2:1310-1315), ESR1 mutations Y537S and D538G mutations detected in baseline plasma samples from ER+/HER- advanced breast cancer patients, was associated with shorter Overall Survival. In this study it was noted that there was a three-fold increase in the prevalence of these mutations in patients who had failed first line hormonal therapy for metastatic disease, compared with those who were initiating first line therapy for advanced breast cancer (33% versus 11%).

Fulvestrant (FASLODEX®) is an estrogen antagonist and like Tamoxifen binds to estrogen receptors (ERs) competitively, but unlike Tamoxifen causes rapid degradation and loss of ER protein (ER down regulator) and is devoid of ER agonist activity. Palbociclib (IBRANCE®) is a reversible, oral, selective, small molecule inhibitor of Cyclin Dependent Kinases, CDK4 and CDK6, and prevents RB1 phosphorylation. Palbociclib is the first CDK inhibitor approved by the FDA. It exhibits synergy when combined with endocrine therapies. The FDA in February 2016, approved Palbociclib in combination with Fulvestrant, for the treatment of women with HR-positive, HER2-negative advanced or metastatic breast cancer, with disease progression following endocrine therapy.

Patients with ESR1 mutations on Fulvestrant had improved Progression Free Survival (PFS) compared with Exemestane (AROMASIN®) in the SoFEA trial. The combination of Palbociclib and Fulvestrant improved PFS compared with Fulvestrant plus placebo in both ESR1 mutant and ESR1 wild-type patients, in the PALOMA3 trial.

The PADA-1 study aimed to show the efficacy of an early change in therapy based on a rising ESR1 mutation in the peripheral blood, while assessing the global safety of the combination Fulvestrant and Palbociclib. PADA-1 is a prospective, randomized, open-label, multicentre, Phase III trial in which 1017 patients with ER-positive, HER2-negative advanced breast cancer were included. These patients were monitored for a rising ESR1 mutation in the peripheral blood, while on first-line treatment with an Aromatase Inhibitor (Letrazole 2.5 mg, Anastrozole 1 mg or Exemestane 25 mg orally once daily, taken continuously) and Palbociclib 125 mg orally once daily on days 1-21 of a 28-day treatment cycle, at enrollment and every 2 months thereafter. Blood samples were monitored for several ESR1 mutations which included E380, P535, L536, Y537, and D538. The median time from trial enrollment to detection of the ESR1 mutation was 14.2 months. Patients with newly present or rising ESR1 mutation in the peripheral blood circulating tumor DNA and no synchronous disease progression (N=172) were randomly assigned (1:1) to continue with the same therapy (N=84) or to switch to Fulvestrant 500 mg IM on day 1 of each 28-day cycle and on day 15 of cycle 1, along with Palbociclib as previously dosed (N=88). Baseline characteristics were similar in both treatment groups. The median patient age was 61 years, and one-third of patients had prior treatment with an Aromatase Inhibitor. Patients were stratified according to visceral involvement (present or absent) and the time from inclusion to detection of ESR1 mutation in the peripheral blood (<12 months or 12 months or more). The co-Primary endpoints were Progression Free Survival and Grade 3 or more hematologic adverse events in all patients.

At a median follow up of 26.0 months from randomization, switching patients from an Aromatase Inhibitor to Fulvestrant, upon detection of ESR1 mutation in the peripheral blood was associated with a 39% reduction in the risk of disease progression or death. The median Progression Free Survival was 11.9 months in the Fulvestrant and Palbociclib group versus 5.7 months in the Aromatase Inhibitor and Palbociclib group (HR=0.61; P=0·004). The co-Primary endpoint of Grade 3 or more hematologic adverse events found no safety signals associated with switching from an Aromatase inhibitor to Fulvestrant. The most frequent Grade 3 or more hematological adverse events were neutropenia. lymphopenia, and thrombocytopenia. Dose reductions were similar in both randomized treatment groups.

The authors concluded that PADA-1 is the first prospective randomized trial to demonstrate that early therapeutic targeting of ESR1 mutation in the peripheral blood results in significant clinical benefit. The researchers added that the original design explored in PADA-1 might help with addressing acquired resistance to new drugs in future trials.

Switch to fulvestrant and palbociclib versus no switch in advanced breast cancer with rising ESR1 mutation during aromatase inhibitor and palbociclib therapy (PADA-1): a randomised, open-label, multicentre, phase 3 trial. Bidard FC, Hardy-Bessard AC, Dalenc F, et al. The Lancet Oncology. Published: September 29, 2022.DOI:https://doi.org/10.1016/S1470-2045(22)00555-1

Elevated White Cell Count and Risk of Thrombotic Events in Polycythemia Vera

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SUMMARY: Polycythemia Vera (P. Vera) is a clonal myeloproliferative neoplasm characterized by isolated erythrocytosis in a majority of the patients, with the remaining demonstrating leukocytosis and/or thrombocytosis along with erythrocytosis. Patients usually present with this disorder in their sixth decade and are often asymptomatic, with the diagnosis made incidentally on routine laboratory evaluation. About 30% of the patients however, may initially present with a thrombotic episode, whereas a small percentage of patients may present with disease related symptoms such as pruritus and fatigue. The conventional risk factors for thrombotic events in MyeloProliferative Neoplasms (MPN) are age more than 60 years and prior thrombosis, and the presence of both these risk factors is associated with a 7-fold increased risk of thrombosis.

Overactivation of the JAK-STAT signal transduction pathway caused by V617F mutation has been implicated in majority of the patients with P. Vera. This pathway normally is responsible for passing information from outside the cell through the cell membrane to the DNA in the nucleus for gene transcription. Janus Kinase (JAK) family of tyrosine kinases are cytoplasmic proteins and include JAK1, JAK2, JAK3 and TYK2. JAK1 helps propagate the signaling of inflammatory cytokines whereas JAK2 is essential for growth and differentiation of hematopoietic stem cells. These tyrosine kinases mediate cell signaling by recruiting STATs (Signal Transducer and Activator of Transcription), with resulting modulation of gene expression. In patients with P. Vera, the aberrant myeloproliferation is the result of dysregulated JAK2-STAT signaling as well as excess production of inflammatory cytokines, associated with this abnormal signaling. JAK2 mutations such as JAK2 V617F are seen in approximately 95% of patients with P. Vera.Molecular-Mechanisms-of-MPNs

Studies have shown that JAK2 mutations that result in the overproduction of erythrocytes, leukocytes, and platelets in P. Vera also promote direct activation of leukocytes and platelets. Activated platelets and leukocytes bind to each other and activate endothelial cells, which may in turn contribute to the prothrombotic state. The prospective CYTO-PV trial published in 2011, established that maintaining hematocrit less than 45% through phlebotomies and/or cytoreductive drugs significantly decreased the risk of thrombotic events in P. Vera patients. Even though several retrospective analyses strongly suggest an association between leukocytosis and thrombosis and leukocytosis particularly at the time of the thrombotic event in P. Vera patients, no prospective trial has been conducted to assess the impact of WBC counts on thrombotic risk in P. Vera.

The REVEAL study is a large, real-world, multicenter, prospective, noninterventional, observational study, in which patients with P. Vera from US community practice and academic centers were enrolled, to evaluate the association between elevated blood counts and occurrence of thrombotic events in patients with P. Vera, using data from the REVEAL study.

This study analyzed the data of 2271 eligible patients for this analysis (78% high risk and 22% low risk). The median patient age was 66 years and 54% were male. The median disease duration was 4.1 years, 20% had a history of thrombotic events and majority of patients (53%) were receiving Hydroxyurea. Patient data was collected at diagnosis, at a 6-month period, and during follow up, 3 years from last patient enrollment, between July 2014 and August 2019 and the researchers analyzed the association between blood counts and thrombotic events. Out of 106 patients who had thrombotic events, 30 had arterial thrombotic events, most commonly, Transient Ischemic Attack and 76 had venous thrombotic events, most commonly, Deep Vein Thrombosis.

It was noted that hematocrit greater than 45% versus 45% or less (P=0.0028), WBC more than 11×109/L versus 11×109/L or less (P<0.0001), and Platelet counts more than 400×109/L versus 400×109/L or less (P=0.0170) were each associated with increased risk of thrombotic events. A WBC count of 11×109/L or more was associated with the highest thrombotic event risk compared with WBC count less than 7×109/L (P<0.0001).  When the HCT was controlled at 45% or less, an elevated WBC count (more than 12 × 109/L) was significantly associated with increased risk of thromboembolism (HR=1.95; P=0.03). In all models analyzed, advanced age and history of thrombotic events, were associated with increased thrombotic event risk.

The authors concluded that in this analysis of the largest real-world cohort of P. Vera patients to date, hematocrit more than 45%, as well as WBC more than 11×109/L and Platelet counts more than 400×109/L, were each associated with increased risk of thrombotic events. WBC more than 12×109/L was significantly associated with increased thrombotic risk, even when the HCT was controlled, suggesting that thrombotic risk may be reduced by controlling both the WBC count and HCT level. The authors added that these data support the incorporation of blood count values into risk stratification and treatment strategies for patients with P. Vera in clinical practice, and to move beyond the conventional risk model.

A Real-World Evaluation of the Association between Elevated Blood Counts and Thrombotic Events in Polycythemia Vera: An Analysis of Data from the REVEAL Study). Gerds AT, Mesa RA, Burke JM, et al. Presented at: 2022 European Hematology Association Congress; June 10, 2022; Vienna, AT. Poster # P1062.

Association Between Polycystic Ovary Syndrome and Risk of Pancreatic Cancer

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SUMMARY: The American Cancer Society estimates that in 2022, about 62,210 people will be diagnosed with pancreatic cancer and 49,830 people will die of the disease. Pancreatic cancer is the fourth most common cause of cancer-related deaths in the United States and Western Europe. Unfortunately, unlike other malignancies, very little progress has been made and outcome for patients with advanced pancreatic cancer has been dismal, with a 5-year survival rate for metastatic pancreatic cancer of approximately 10%. Pancreatic cancer has surpassed breast cancer as the third leading cause of cancer death in the United States and is on track to surpass colorectal cancer, to move to the second leading cause of cancer related deaths in the United States.

Majority of patients with pancreatic cancer (80% of cases) are diagnosed at an advanced stage, and are not amenable to curative surgical resection, at the time of diagnosis. The current treatment regimens for advanced disease have proved ineffective, conferring a median Overall Survival (OS) of 6-8 months. Clinical surveillance is recommended for individuals at high risk, although pancreatic cancer has relatively few established risk factors.

Polycystic Ovary Syndrome (PCOS) is a hormone disorder affecting 7-10% of women of childbearing age and is the most common cause of infertility. In the United States, an estimated 5-6 million women have PCOS and is the most common hormonal disorder among women of reproductive age. The etiology of PCOS is unknown and the signs and symptoms of PCOS have been attributed to abnormal levels of Luteinizing Hormone (LH) and androgen excess, which interfere with normal function of the ovaries. Hyperinsulinemia and insulin resistance can lead to the development of Type 2 diabetes and worsen androgen excess. A previously published study using Swedish register data suggested several carcinogenic processes associated with PCOS, with a 3.4-fold increased risk of pancreatic cancer, in small group of women with PCOS (JAMA Oncol. 2019;5(1):106-107).

To confirm these findings, the authors conducted a case-control study using data from the Memorial Sloan Kettering Cancer Center Pancreatic Tumor Registry. The study population included 446 women (N=446) who were 21 years of age or older and had pathologically or cytologically confirmed pancreatic adenocarcinoma. The control group consisted of visitors accompanying patients to Memorial Sloan Kettering Cancer Center clinics or spouses of patients with pancreatic cancer with no personal history of cancer (N=209). The researchers followed STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guideline to report their observational research findings and used multivariable logistic regression to estimate Odds Ratios (ORs) and 95% Confidence Intervals (CIs) for the association between PCOS and risk of pancreatic cancer. The median age of the study population was 60 years.

The researchers noted a positive association between PCOS and risk of pancreatic cancer, after adjusting for age, race and ethnicity, BMI, and estrogen use (OR=1.88 – 88% more likely). The Odds Ratio remained significant at 1.78 after adjusting for potential mediator Type 2 diabetes, in addition to all the above factors. Excluding those with pancreatic cancer diagnosed less than 5 years after PCOS diagnosis, history of pancreatitis and a history of familial pancreatic cancer did not materially alter risk estimates. These findings suggested that this association of PCOS and risk of pancreatic cancer was independent of BMI, and not driven by Type 2 diabetes or other variables. The researchers hypothesized that these data suggest some individuals may have unknown metabolic derangements that may underly the development of both conditions.

The authors concluded that in this case-control study, PCOS was strongly associated with increased risk of pancreatic cancer. They added that diagnosis of PCOS may warrant increased education and clinical vigilance for pancreatic cancer, although prospective studies are needed to examine underlying biologic mechanisms and confirm this study findings.

Association Between Polycystic Ovary Syndrome and Risk of Pancreatic Cancer. Peeri NC, Landicino MV, Saldia CA, et al. JAMA Oncol. Published online October 6, 2022. doi:10.1001/jamaoncol.2022.4540