Momelotinib versus danazol in symptomatic patients with anaemia and myelofibrosis (MOMENTUM): results from an international, double-blind, randomised, controlled, phase 3 study.

BACKGROUND: Janus kinase (JAK) inhibitors approved for myelofibrosis provide spleen and symptom improvements but do not meaningfully improve anaemia. Momelotinib, a first-in-class inhibitor of activin A receptor type 1 as well as JAK1 and JAK2, has shown symptom, spleen, and anaemia benefits in myelofibrosis. We aimed to confirm the differentiated clinical benefits of momelotinib versus the active comparator danazol in JAK-inhibitor-exposed, symptomatic patients with anaemia and intermediate-risk or high-risk myelofibrosis. METHODS: MOMENTUM is an international, double-blind, randomised, controlled, phase 3 study that enrolled patients at 107 sites across 21 countries worldwide. Eligible patients were 18 years or older with a confirmed diagnosis of primary myelofibrosis or post-polycythaemia vera or post-essential thrombocythaemia myelofibrosis. Patients were randomly assigned (2:1) to receive momelotinib (200 mg orally once per day) plus danazol placebo (ie, the momelotinib group) or danazol (300 mg orally twice per day) plus momelotinib placebo (ie, the danazol group), stratified by total symptom score (TSS; <22 vs ≥22), spleen size (<12 cm vs ≥12 cm), red blood cell or whole blood units transfused in the 8 weeks before randomisation (0 units vs 1-4 units vs ≥5 units), and study site. The primary endpoint was the Myelofibrosis Symptom Assessment Form (MFSAF) TSS response rate at week 24 (defined as ≥50% reduction in mean MFSAF TSS over the 28 days immediately before the end of week 24 compared with baseline). MOMENTUM is registered with ClinicalTrials.gov, number NCT04173494, and is active but not recruiting. FINDINGS: 195 patients were randomly assigned to either the momelotinib group (130 [67%]) or danazol group (65 [33%]) and received study treatment in the 24-week randomised treatment period between April 24, 2020, and Dec 3, 2021. A significantly greater proportion of patients in the momelotinib group reported a 50% or more reduction in TSS than in the danazol group (32 [25%] of 130 vs six [9%] of 65; proportion difference 16% [95% CI 6-26], p=0·0095). The most frequent grade 3 or higher treatment-emergent adverse events with momelotinib and danazol were haematological abnormalities by laboratory values: anaemia (79 [61%] of 130 vs 49 [75%] of 65) and thrombocytopenia (36 [28%] vs 17 [26%]). The most frequent non-haematological grade 3 or higher treatment-emergent adverse events with momelotinib and danazol were acute kidney injury (four [3%] of 130 vs six [9%] of 65) and pneumonia (three [2%] vs six [9%]). INTERPRETATION: Treatment with momelotinib, compared with danazol, resulted in clinically significant improvements in myelofibrosis-associated symptoms, anaemia measures, and spleen response, with favourable safety. These findings support the future use of momelotinib as an effective treatment in patients with myelofibrosis, especially in those with anaemia. FUNDING: Sierra Oncology.

Meaningful Symptomatic Change in Patients With Myelofibrosis From the SIMPLIFY Studies.

OBJECTIVES: Patients with myelofibrosis develop symptoms due to bone marrow fibrosis, systemic inflammation, and/or organomegaly. Alleviating symptoms improves overall quality of life. Clinical trials have historically defined symptom response as a reduction of at least 50% in Total Symptom Score at week 24 compared with baseline. Whether 50% constitutes a meaningful benefit has not been established. This study determined the meaningful change threshold (MCT) for 2 momelotinib phase III trials, SIMPLIFY-1 and SIMPLIFY-2. METHODS: The absolute and percentage MCT was determined using anchor-based methods applied to the modified Myeloproliferative Neoplasm Symptom Assessment Form v2.0 and Patient Global Impression of Change. MCTs were applied retrospectively to determine responder rates. Generalized estimating equations estimated the treatment-related difference in likelihood of improvement. RESULTS: In SIMPLIFY-1, a Janus kinase inhibitor-naive population, the MCT was 8 points. In SIMPLIFY-2, a previously Janus kinase inhibitor-treated population, the MCT was 6 points. A 32% MCT was determined in both studies, showing that the historic 50% reduction threshold may be a conservative choice. In SIMPLIFY-1, a similar proportion of patients achieved responder status with 24 weeks of momelotinib or ruxolitinib therapy based on the absolute MCT (39% vs 41%, respectively). In SIMPLIFY-2, a significantly greater proportion of patients treated with momelotinib achieved responder states compared with best available therapy based on absolute and percent change MCTs. CONCLUSIONS: This study demonstrates that momelotinib provided clinically meaningful symptom benefit for patients with myelofibrosis and provides insight into the appropriateness of the symptom change threshold used in historical studies.

Anemia-related response end points in myelofibrosis clinical trials: current trends and need for renewed consensus.

JAK inhibitors are the current standard of care in myelofibrosis, but many do not address and may worsen anemia; thus, anemia-related responses have traditionally been overlooked as efficacy end points in pivotal clinical trials, leading to a lack of consistency and analytic detail in their reporting. Here we apply our experiences in the phase III trials of momelotinib, a JAK1/JAK2/ACVR1 inhibitor and the first therapy indicated by the US FDA for myelofibrosis patients with anemia, to highlight how application of different criteria impacts the anemia-related benefits reported for any potential treatment in myelofibrosis. We advocate for a convention of a new expert consensus panel to bring consistency and transparency to the definition of anemia-related response in myelofibrosis.

What is this Perspective about? Anemia (too few healthy red blood cells) is common in patients with myelofibrosis. While it is becoming more common to measure the anemia benefits associated with potential treatments for myelofibrosis in clinical trials, different definitions of anemia benefit are available. This Perspective reviews these definitions, the differences between them, and why consistency and clarity in measuring anemia benefit matter. The definitions used in clinical trials of momelotinib, a treatment for patients with myelofibrosis and anemia, are also explained to show how the anemia benefit observed in these trials could have changed if different definitions were used. What does this Perspective show? Definitions of anemia benefit may include the number of red blood cell transfusions a patient receives, the amount of hemoglobin (a red blood cell protein) in their blood, or a combination thereof. Considerations such as timing, the types of patients included, and other factors are not consistent across definitions and not always clearly reported. Results when different definitions of anemia benefit were followed in the momelotinib clinical trials show that the amount of benefit observed with treatments changes depending on which definition is used. What conclusions can be drawn from this Perspective? More consistency and clarity in the definitions of anemia benefit in myelofibrosis clinical trials are needed, suggesting that a new panel of experts should come together to discuss this topic.

A Phase 1/2 trial of SRA737 (a Chk1 inhibitor) administered orally in patients with advanced cancer.

BACKGROUND: This was a first-in-human Phase 1/2 open-label dose-escalation study of the novel checkpoint kinase 1 (Chk1) inhibitor SRA737. METHODS: Patients with advanced solid tumours enrolled in dose-escalation cohorts and received SRA737 monotherapy orally on a continuous daily (QD) dosing schedule in 28-day cycles. Expansion cohorts included up to 20 patients with prospectively selected, pre-specified response predictive biomarkers. RESULTS: In total, 107 patients were treated at dose levels from 20-1300 mg. The maximum tolerated dose (MTD) of SRA737 was 1000 mg QD, the recommended Phase 2 dose (RP2D) was 800 mg QD. Common toxicities of diarrhoea, nausea and vomiting were generally mild to moderate. Dose-limiting toxicity at daily doses of 1000 and 1300 mg QD SRA737 included gastrointestinal events, neutropenia and thrombocytopenia. Pharmacokinetic analysis at the 800 mg QD dose showed a mean Cmin of 312 ng/mL (546 nM), exceeding levels required to cause growth delay in xenograft models. No partial or complete responses were seen. CONCLUSIONS: SRA737 was well tolerated at doses that achieved preclinically relevant drug concentrations but single agent activity did not warrant further development as monotherapy. Given its mechanism of action resulting in abrogating DNA damage repair, further clinical development of SRA737 should be as combination therapy. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov NCT02797964.

A Phase I/II Trial of Oral SRA737 (a Chk1 Inhibitor) Given in Combination with Low-Dose Gemcitabine in Patients with Advanced Cancer.

PURPOSE: This was a Phase I/II trial of the novel checkpoint kinase 1 (Chk1) inhibitor SRA737 given in combination with gemcitabine. Its objectives were to establish the safety profile, recommended Phase 2 dose (RP2D), pharmacokinetics profile, and clinical activity of SRA737. PATIENTS AND METHODS: Patients with advanced solid tumors were enrolled into dose-escalation cohorts and treated in 28-day cycles with oral SRA737 on days 2, 3, 9, 10, 16, and 17, and intravenous gemcitabine on days 1, 8, and 15. Treatment was continued until progression. Each expansion cohort included up to 20 patients with specific genetically defined tumors. RESULTS: The RP2D was determined to be 500 mg SRA737 combined with low-dose (250 mg/m2) gemcitabine. Of 143 enrolled patients, 77 were treated at doses of at least 500 mg SRA737 combined with 250 mg/m2 gemcitabine. Common toxicities of nausea, vomiting, fatigue, and diarrhea were primarily mild to moderate, and rarely led to treatment discontinuation. Anemia, neutropenia, and thrombocytopenia were grade ≥3 in 11.7%, 16.7%, and 10% of patients treated at the RP2D, respectively. The objective response rate (ORR) was 10.8% overall and notably the ORR in anogenital cancer was 25%. Partial tumor responses were observed in anogenital cancer, cervical cancer, high-grade serous ovarian cancer, rectal cancer, and small cell lung cancer. CONCLUSIONS: SRA737 in combination with low-dose gemcitabine was well tolerated with lower myelotoxicity than has been seen at standard doses of gemcitabine or with other combinations of Chk1 inhibitors with gemcitabine. Tumor responses were observed in anogenital and other solid tumors.

Symptomatic benefit of momelotinib in patients with myelofibrosis: Results from the SIMPLIFY phase III studies.

BACKGROUND: Myelofibrosis (MF)-associated constitutional symptoms can severely impact health-related quality of life. Clinical trials in MF traditionally measure symptom response to treatment as a landmark endpoint of total symptom score (TSS) reduction ≥50% from baseline. However, this dichotomous assessment provides a limited view of clinically relevant symptomatic changes. Herein we evaluated longitudinal change from baseline in TSS over the continuous 24-week period and individual symptom scores to obtain a more comprehensive understanding of symptom benefits experienced by patients with MF receiving therapy. METHODS: Longitudinal symptom change was evaluated using mixed-effect model repeated measure (MMRM) methodology with individual item-level analyses to complement the interpretation of the landmark symptom results in the completed phase III SIMPLIFY studies of momelotinib in MF. MMRM compared mean change in TSS from baseline with Week 24 using data from all patient visits. Generalized estimating equations were used to estimate item-level odds ratios using multiple predictive imputations for missing data. RESULTS: Momelotinib and ruxolitinib groups reported similar overall symptom improvements, with a TSS difference of <1.5 points between groups for each post-baseline visit in SIMPLIFY-1. In SIMPLIFY-2, the improvement in TSS observed in momelotinib-treated patients was consistent with that observed in SIMPLIFY-1, whereas progressive TSS deterioration was observed with control. Item-level scores were heterogeneous in both studies. A similar and greater proportion of momelotinib-treated patients were categorized as "improved" or "stable" compared with control in SIMPLIFY-1 and SIMPLIFY-2, respectively. Odds ratios for between-group comparison ranged from 0.75 to 1.21 in SIMPLIFY-1, demonstrating similarity in likelihood of symptom improvement. In SIMPLIFY-2, the likelihood of symptom improvement in each item was higher in the momelotinib arm. CONCLUSIONS: These findings suggest that momelotinib provides clinically relevant symptom benefits in the JAK inhibitor-naïve and JAK inhibitor-exposed settings.

Momelotinib versus danazol in symptomatic patients with anaemia and myelofibrosis previously treated with a JAK inhibitor (MOMENTUM): an updated analysis of an international, double-blind, randomised phase 3 study.

BACKGROUND: The MOMENTUM study met all key endpoints at week 24, demonstrating symptom, spleen, and anaemia benefits with momelotinib versus danazol in patients with myelofibrosis. In this updated analysis, we report duration of week 24 responses and new responses with momelotinib through week 48. METHODS: MOMENTUM is an international, double-blind, randomised, phase 3 study done at 107 sites across 21 countries. Patients were 18 years or older with primary, post-polycythaemia vera, or post-essential thrombocythaemia myelofibrosis, previously treated with an approved Janus kinase (JAK) inhibitor for 90 days or more (≥28 days with haematological complications), and had an Eastern Cooperative Oncology Group performance status of 2 or less. Patients were randomly assigned (2:1) to either the momelotinib group (200 mg orally once per day) or danazol group (300 mg orally twice per day) through week 24 via non-deterministic biased coin minimisation and an interactive response system. Stratification factors were Total Symptom Score (TSS; <22 vs ≥22), spleen size (<12 cm vs ≥12 cm), transfusion burden (0 units vs 1-4 units vs ≥5 units), and study site. After week 24, all patients initially randomly assigned to either group who remained on the study received open-label momelotinib. The primary endpoint, which has already been reported, was Myelofibrosis Symptom Assessment Form TSS response rate at week 24. Predefined secondary endpoints were duration of week 24 TSS and transfusion independence responses, safety, and survival, which are summarised post hoc at the week 48 data cutoff (May 17, 2022). TSS, transfusion independence, and splenic responses at week 48 were defined post hoc and assessed in all evaluable patients who entered the open-label period and provided sufficient data. The timing of this updated analysis was defined post hoc after all patients had the opportunity to complete their week 48 assessments, as most patients entered an extended access study (NCT03441113) after week 48. This study is registered with ClinicalTrials.gov, number NCT04173494, and is now complete. FINDINGS: Between April 24, 2020, and Dec 3, 2021, a total of 195 patients were randomised (130 [67%] in the momelotinib group and 65 [33%] in the danazol group). 93 (72%) of 130 patients in the momelotinib group and 41 (63%) of 65 in the danazol group entered the momelotinib open-label extension period. Median follow-up was 48·4 weeks (IQR 40·6-55·7). Among TSS-evaluable patients at week 48, 30 (45%) of 67 patients in the momelotinib group who continued treatment and 15 (50%) of 30 in the danazol group who crossed over were responders. TSS responders at any time during the open-label period by week 48 were 46 (61%) of 75 evaluable patients in the momelotinib group who continued and 19 (59%) of 32 in the danazol group who crossed over, including most week 24 responders plus new responders after week 24. No new safety signals emerged with long-term follow-up. The most common non-haematological treatment-emergent adverse events in momelotinib-treated patients over the entire study period as of the data cutoff were diarrhoea (45 [26%] of 171) and asthenia (28 [16%]); the most common grades 3-4 treatment-emergent adverse events were thrombocytopenia (33 [19%]) and anaemia (19 [11%]). Serious treatment-emergent adverse events were reported in 79 (46%) of 171 patients, and fatal treatment-emergent adverse events were reported in 30 (18%); two fatal treatment-emergent adverse events were considered possibly related to momelotinib (rotaviral enteritis and Staphylococcus pneumonia). INTERPRETATION: Momelotinib was associated with durable symptom, spleen, and anaemia benefits, late responses after week 24, and favourable safety through week 48. These results highlight the potential benefits of treatment with momelotinib in patients with myelofibrosis, particularly those with anaemia. FUNDING: Sierra Oncology, a GSK company.

Anal cancer: an HIV-associated cancer.

Although not yet included in the Centers for Disease Control definition of AIDS, anal cancer clearly occurs more commonly in HIV-infected patients. An effective screening program for those groups who are at highest risk might be expected to impact rates of anal cancer just as significantly as did cervical Pap screening programs for the incidence of cervical cancer. Despite a relatively low rate of progression from AIN to invasive cancer, the scope of the problem is enormous based on the prevalence of anal HPV infection and the size of the HIV-infected, at-risk population. Thus, the potential benefits of screening, detection, and the development of more effective therapy also are enormous. Currently, therapeutic HPV vaccines for AIN represent an exciting avenue of research in HPV-related anogenital disease. Invasive anal cancer and HSIL (which is believed to be the precursor lesion) are expected to become increasingly important health problems for both HIV-infected men and women as their life expectancy lengthens. Although HAART may have improved the ability of many to tolerate CMT, it appears that toxicity of this therapy continues to be a problem for a proportion of HIV-infected subjects. The acute side effects present specific challenges to the clinician and patient, have an immediate impact on the patient's plan of care and dose intensity of the treatment, and ultimately may impact the outcome of the planned treatment. Late toxicity may influence the long-term quality of life. Small patient numbers, variable radiation therapy doses, limited information about viral load, and a potential confounding effect of higher CD4+ levels make it difficult to draw any conclusions about the effect of HAART on anal cancer outcome. Large, prospective studies will be required before solid conclusions about the impact of various factors on anal cancer prognosis and outcome can be drawn.

Altered clinical course of malignant melanoma in HIV-positive patients.

OBJECTIVE: To determine whether the natural history of melanoma is different in patients who test positive for human immunodeficiency virus (HIV) compared with matched control subjects. DESIGN: Retrospective cohort analysis. SETTING: Ambulatory care at 2 university-affiliated medical centers. PATIENTS: Each HIV-positive melanoma patient (n = 17) was randomly matched with 2 HIV-negative patients (HIV status unknown, but without risk factors for HIV) based on the melanoma subtype, tumor thickness, Clark level, tumor location, and sex and age of the patient. MAIN OUTCOME MEASURES: Disease-free survival and overall survival of HIV-positive and HIV-negative melanoma patients were compared using a matched-pairs analysis. CD4 cell counts were recorded at the time of melanoma diagnosis and disease recurrence. RESULTS: Melanoma patients who were HIV positive had a significantly shorter disease-free survival (P =.03) and overall survival (P =.045) compared with HIV-negative melanoma patients by matched-pairs analysis. There was an inverse relationship between CD4 cell counts and time to first melanoma recurrence. CONCLUSIONS: The natural history of malignant melanoma in HIV-positive patients is more aggressive compared with matched HIV-negative melanoma patients. Altered immune response and comorbid disease may play a role in the poor clinical outcome of HIV-positive patients. These findings have important implications in the management of melanoma in the setting of HIV disease.