Citations

Study Design This study is part of the AO Spine Metastatic Tumor Research and Outcomes Network [MTRON], an international multicenter prospective observational registry including patients with spinal metastases. Objectives This study aims to elucidate the incidence of surgical complications, their risk factors and consequent effects on survival outcomes, hospital length of stay, and overall health-related quality of life (HRQOL) parameters in a large cohort of patients affected by spinal metastases who were surgically treated. Methods Available data from February 2017 to July 2023 were analyzed. The primary outcome of this study was the evaluation of the incidence of intraoperative and postoperative adverse events (AEs). The secondary outcomes included the assessment of risk factors for surgery-related AEs and the impact of AEs on survival, length of hospital stay and quality of life. Results Among the 1267 patients analyzed, 6.9% experienced intraoperative AEs and 19.3% experienced at least 1 postoperative AE. Several factors resulted to be associated to the occurrence of postoperative AEs: age, smoking habit, poor Eastern Cooperative Oncology Group (ECOG) Performance status, previous radiation therapy at the index target, duration of surgery, number of instrumented levels, simultaneous anterior and posterior approach, presence of metastases at other sites, multiple spinal metastases. Postoperative AEs were associated with reduced survival rates, increased hospital length of stay and poorer HRQOL outcomes, particularly in domains such as neurological function and mental health. In general, surgery substantially improves HRQOL across multiple domains, with these benefits persisting over time despite the occurrence of AEs. However, patients with preoperative risk factors, including comorbidities, smoking, neurological impairment, and prior radiation therapy, experienced less improvement. Conclusions The negative impact of AEs on overall survival and HRQOL could be associated with the presence of some preoperative parameters of frailty that are detected as risk factors for AEs occurrence. This finding emphasizes the need for personalized preoperative assessments and optimized perioperative care strategies.

OBJECTIVE Surgery is typically indicated for mechanical pain in metastatic spine disease or severe neurological compromise, but how radicular pain responds to oncological treatment is not well described. The primary aim of this study was to describe how radicular pain responds to oncological treatment, while secondary aims included pain outcomes between patients with mechanical and tumoral pain and motor improvement in patients with weakness due to nerve root compression. METHODS Patients treated with surgery and/or radiotherapy for spinal metastases were identified from an international multicenter prospective cohort. The primary outcome was the numeric rating scale (NRS) score for pain at 3 months posttreatment. Motor recovery from radicular compression in patients with myotomic weakness and low-grade epidural compression was also analyzed. RESULTS Of 284 patients, 129 (45%) had radicular pain ± axial pain and 155 (55%) had axial pain alone. The two groups did not significantly differ in age, comorbidities, tumor characteristics, or treatment. Two hundred two patients (71%) underwent surgery ± radiotherapy, whereas 82 (29%) had radiotherapy alone. The NRS score of patients with radicular pain improved from 6.7 to 3.4 at 3 months, a statistically significantly higher magnitude than in patients with isolated axial pain (p = 0.021). The NRS score at 3 months was similar for both groups (p = 0.876). Patients with radicular pain experienced a larger improvement with surgery compared with radiotherapy alone (p = 0.007) but had higher pretreatment pain (mean NRS score 7.0 vs 5.6, p = 0.013). Twenty-three patients identified with radicular/myotomic weakness (mean American Spinal Injury Association score 96.3 ± 3.2) at baseline improved 2.1 ± 3.8 points at 3 months. CONCLUSIONS The magnitude of pain improvement for patients with radicular pain following surgery and radiotherapy for metastatic spine disease is higher than for patients with axial pain alone. Surgery is associated with a larger improvement in radicular pain than radiotherapy alone. These results will allow clinicians to tailor treatment options for patients with metastatic spine disease.

Study Design Narrative Review. Objectives To summarize the work of the AO Spine Knowledge Forum Tumor, specifically studies from the Epidemiology, Process and Outcomes in Spine Oncology (EPOSO) study. Methods A narrative review of all published manuscripts from the EPOSO study was undertaken. EPOSO represents a multicenter, prospective registry effort across 10 North American and European sites to enroll patients with metastatic disease of the spine. Results The current review summarized all studies from the EPOSO network, divided into the following five sections: (1) quality of life and satisfaction, (2) overall survival, (3) spinal instability, (4) neurologic outcome in patients with metastatic epidural spinal cord compression or radicular pain, and (5) patient and tumor-specific factors. Several important findings were elucidated. Patient evaluation should include SINS, nutritional status, severity and duration of neurologic deficit, extent of metastatic tumor burden, and differentiation of axial from radicular pain. Moreover, SOSGOQ2.0 serves as a useful and validated instrument for patient-reported outcome instrument. Despite the palliative nature of metastatic spine surgery, clear improvement in quality-of-life is seen. Even in patients with short-survival, the remaining weeks and months of life result in improved quality-of-life. Metastatic spine surgery often improves neurologic function, potentially enhancing survival through increased performance status. Conclusions Several noteworthy results have come from the EPOSO network, highlighting important trends in metastatic spine care. The AO Spine Knowledge Forum Tumor has helped advancing metastatic spine tumor research as well as ensure these new findings reach and benefit clinicians and their patients.

Abstract Patients with NF1-PN experience pain and other symptoms that negatively impact functioning and quality-of-life. We present patient- and parent proxy-reported HRQoL outcomes from ReNeu (NCT03962543), a pivotal, phase 2b trial of mirdametinib, an investigational MEK1/2 inhibitor, in adults and children (≥2 y) with NF1-PN causing morbidities. Fifty-eight adults and 56 children received mirdametinib (2 mg/m2 BID; 3-weeks-on/1-week-off, 28-d cycles). Change in HRQoL was assessed by Pediatric QoL Inventory (PedsQL) 4.0 Generic Core Scales from baseline across the 24-cycle treatment phase; change from baseline at Cycle 13 (C13) was a prespecified secondary endpoint. PedsQL is a HRQoL measure for adults and children with a Total Score (TS) and 4 subscales: physical, emotional, social, and school/work. Items are reported on a 0-100 scale (higher scores=better HRQoL). Clinically meaningful improvement was defined as change from baseline >9.7 points for adults, >8.5 points for child self-report, and >9.0 points for parent proxy-report. PedsQL-TS improvement (least-squares mean, LSM [SE] change) from baseline at C13 was 3.9 (1.6; P=.018; n=34) for adults, 4.0 (2.4; P=.096; n=38) for children by self-report, and 5.6 (1.9; P=.005; n=43) by parent proxy-report. PedsQL-TS improvements for adults and children by parent proxy-report (not by children self-report) were observed early (at C5 and C3, respectively) and sustained through C24. Clinically meaningful improvement in PedsQL-TS from baseline at C13 was achieved by 37% (10/27) adults, 45% (13/29) children by self-report, and 47% (15/32) children by parent proxy-report (among patients who could have achieved a clinically meaningful change from baseline). Significant (P<.05) improvement from baseline to C13 was reported for physical (adults, children, and parent proxy-report), school/work (adults), and emotional and social (parent proxy-report) subscales. Adults and children (by parent proxy-report) with NF1-PN had clinically meaningful, early, and sustained improvement in HRQoL over the course of mirdametinib treatment.

Abstract ReNeu (NCT03962543) is a trial of the investigational, oral, selective MEK1/2 inhibitor (MEKi) mirdametinib in adults (≥18 years) and children (2-17 years) with NF1-PN. Skin adverse events (AEs) were common in ReNeu, and some discontinuations were noted with low-grade AEs. A multidisciplinary team retrospectively reviewed skincare practices at one high-enrolling site (n=12) with no discontinuations due to skin AEs; these were incorporated into ReNeu trial recommendations and recently updated. The purpose was to prevent/manage skin AEs and maintain protocol treatment adherence. MEKi skin AEs vary by pubertal status, therefore recommendations also vary by pubertal status. All patients were counseled to adopt hygienic skincare practices, including bathing daily, and using mild cleansers and hypoallergenic skin moisturizers (cream or ointment-based emollient; minimum BID) to prevent dry skin. Prepubescent patients were advised to incorporate diluted bleach baths (3-4 times/week) when initiating mirdametinib or after rash development. Treatments recommended for mild-to-severe dermatitis were hydrocortisone cream (2.5% BID) on face/skinfold areas and triamcinolone ointment (0.1% BID) on trunk/extremities. Treatments for mild acneiform eruptions included topical clindamycin lotion (1.0% BID) until resolution, with optional hydrocortisone cream (2.5% BID). For moderate-to-severe acneiform eruptions, cephalexin (20 mg/kg/day divided BID, max 500 mg, ≤6 weeks), amoxicillin (25 mg/kg/day divided BID, max 875 mg, ≤6 weeks), or oral fluconazole (20 mg/kg/day, max 100 mg, 5 days then once weekly for 3 months) were suggested. Postpubescent patients were advised to initiate topical 1.0% clindamycin lotion and oral doxycycline or minocycline (50-mg daily, 3 months) with mirdametinib initiation. Patients with subsequent mild-to-severe acneiform eruptions were advised to apply hydrocortisone cream (2.5% BID) or triamcinolone ointment (0.1% BID). Referral to a dermatologist was suggested for all patients with uncontrolled dermatitis, worsening acneiform eruptions, or infection. Proactive skincare practices appeared effective at this site, but prospective validation is necessary before making clinical recommendations.

Abstract BACKGROUND Patients with NF1-PN in the phase 2b ReNeu trial (NCT03962543) of mirdametinib in adults (N=58, ≥18y) and children (N=56, 2-17y) had a deeper median (range) best reduction (adults: -41% [-90% to 13%]; children: -42%, [-91% to 48%]) from baseline in target PN volume than previously published in trials of other agents in NF1-PN. METHODS In the 24-cycle (1-cycle=28d) treatment phase, objective response rate (ORR) was the percentage with confirmed objective responses (OR) of ≥20% target PN volume reduction from baseline on consecutive MRIs (by blinded independent central review). This analysis includes patients achieving deep response (>50% best reduction from baseline in target PN volume) regardless of OR and inclusive of patients in the long-term follow-up. Exploratory analysis of baseline characteristics compared patients with deep response and patients with ≤50% volume reduction. RESULTS ORR was 41% (24/58) in adults and 52% (29/56) in children treated with mirdametinib. 62% (15/24) of adults and 52% (15/29) of children who achieved OR had deep response. To further characterize deep response, 2 adults and 3 children with deep response without confirmation or in long-term follow-up were included. Of those with a deep response, 35% (6/17) of adults and 72% (13/18) of children were investigator-defined as having progressing PN. Patients achieved deep response regardless of baseline age, sex, target PN volume, tumor location, or progression status. For adults and children, median time to best percent change from baseline in PN volume for patients achieving deep response was 25.4 and 21.8mo; for patients with reductions of ≥20% to ≤50% was 15.3 and 15.2mo; for patients with reductions of <20% was 7.8 and 4.2mo, respectively. CONCLUSIONS Patients had a similar likelihood of achieving deep response across assessed baseline characteristics. A trend between deep response and longer treatment duration suggests a benefit of prolonged therapy with mirdametinib.

PURPOSE Pharmacologic therapies for neurofibromatosis type 1-associated plexiform neurofibromas (NF1-PNs) are limited; currently, none are US Food and Drug Administration–approved for adults. METHODS ReNeu is an open-label, multicenter, pivotal, phase IIb trial of mirdametinib in 58 adults (≥18 years of age) and 56 children (2 to 17 years of age) with NF1-PN causing significant morbidities. Patients received mirdametinib capsules or tablets for oral suspension (2 mg/m 2 twice daily, maximum 4 mg twice daily), regardless of food intake, in 3 weeks on/1 week off 28-day cycles. The primary end point was confirmed objective response rate (ORR; proportion of patients with a ≥20% reduction of target PN volume from baseline on consecutive scans during the 24-cycle treatment phase) assessed by blinded independent central review (BICR) of volumetric magnetic resonance imaging. RESULTS Twenty-four of 58 adults (41%) and 29 of 56 children (52%) had a BICR-confirmed objective response during the 24-cycle treatment phase; in addition, two adults and one child had confirmed responses during long-term follow-up. Median (range) target PN volumetric best response was –41% (−90 to 13) in adults and –42% (−91 to 48) in children. Both cohorts reported significant and clinically meaningful improvement in patient- or parent proxy-reported outcome measures of worst tumor pain severity, pain interference, and health-related quality of life (HRQOL) that began early and were sustained during treatment. The most commonly reported treatment-related adverse events were dermatitis acneiform, diarrhea, and nausea in adults and dermatitis acneiform, diarrhea, and paronychia in children. CONCLUSION In ReNeu, the largest multicenter NF1-PN trial reported to date, mirdametinib treatment demonstrated significant confirmed ORRs by BICR, deep and durable PN volume reductions, and early, sustained, and clinically meaningful improvement in pain and HRQOL. Mirdametinib was well-tolerated in adults and children.

Abstract BACKGROUND PN in patients (pts) with NF1 can cause pain, disfigurement, impaired quality of life (QoL), and it can undergo malignant transformation. ReNeu (NCT03962543), a multicenter, open-label, phase 2b study, evaluated efficacy and safety of the highly selective, oral, investigational MEK1/2 inhibitor mirdametinib in adults (≥18 y) and children (2-17 y) with inoperable NF1 PN causing significant morbidities. MATERIAL AND METHODS Mirdametinib was administered as a capsule or dispersible tablet (2 mg/m2 BID, max 4 mg BID) without regard to food in 3 wk on/1 wk off 28-d cycles. The primary endpoint was confirmed objective response rate (ORR; percentage of pts with confirmed MRI-assessed ≥20% reduction of target PN volume by blinded independent central review [BICR] within the 24-cycle treatment phase). The minimum clinically relevant ORR (null) was defined as 23% for adults and 20% for children. Pts could continue treatment in an optional long-term follow-up (LTFU) phase. Additional key endpoints were duration of response (DoR), time to response (TTR), change from baseline in target PN volume, worst pain severity (Numerical Rating Scale-11 [NRS-11]), pain interference (Pain Interference Index [PII]), health-related (HR) QoL (PedsQL), and safety. RESULTS All 114 pts (58 adult, 56 children) received mirdametinib. As of the 20 Sept 2023 data cutoff (DCO), BICR-confirmed ORR during the treatment phase was 41% (95% CI, 29-55; P<.001 vs null) in adults and 52% (95% CI, 38-65; P<.001 vs null) in children. Two adults and 1 child had a confirmed response in the ongoing LTFU. Median (range) target PN volumetric best response from baseline was -41% (-90, 13) and -42% (-91, 48) in adult and children, respectively. As of the DCO, median treatment duration was 22 mo for each cohort, and median DoR was not reached. Median (range) TTR was 7.8 (4-19) mo in adults and 7.9 (4-19) mo in children. Adults and children had statistically significant improvements from baseline to Cycle 13 in NRS-11, PII, and key PedsQL measures. Most frequent (≥35% pts) treatment-emergent adverse events (TEAEs) were dermatitis acneiform, diarrhea, nausea, and vomiting in adults and diarrhea, dermatitis acneiform, and vomiting in children. 16% and 25% of adults and children, respectively, had grade ≥3 treatment-related AEs, and 22% and 9%, respectively, discontinued due to TEAEs. CONCLUSIONS In ReNeu, the largest multicenter NF1 PN trial reported to date, mirdametinib demonstrated a statistically significant ORR by BICR, with deep and durable PN volume reductions, significant improvements in pain severity, pain interference, and HRQoL, and a manageable safety profile in both adults and children. Together with a dispersible tablet formulation, these results underscore the potential of mirdametinib to become an important new treatment option for NF1 PN pts across all ages.

3016 Background: PN in patients (pts) with NF1 can cause pain, disfigurement, impaired quality of life (QoL), and can undergo malignant transformation. ReNeu (NCT03962543), a multicenter, open-label, Phase 2b study, evaluated efficacy and safety of the highly selective, oral, investigational MEK1/2 inhibitor mirdametinib in adult (≥18 y) and pediatric (2-17 y) pts with inoperable NF1 PN causing significant morbidities. Methods: Mirdametinib was administered as a capsule or dispersible tablet (2 mg/m 2 BID, max 4 mg BID) without regard to food in 3 wk on/1 wk off 28-d cycles. The primary endpoint was confirmed objective response rate (ORR; percentage of pts with MRI-assessed ≥20% reduction of target PN volume by blinded independent central review [BICR] within the 24-cycle treatment phase). The minimum clinically relevant ORR (null) was defined as 23% for adults and 20% for pediatrics. Ptscould continue treatment in an optional long-term follow-up (LTFU) phase. Additional key endpoints were duration of response (DoR), time to response (TTR), change from baseline (BL) in target PN volume, pain severity (Numerical Rating Scale-11 [NRS-11]), pain interference (Pain Interference Index [PII]), health-related (HR) QoL (PedsQL), and safety. Results: All114 pts (58 adult, 56 pediatric) received mirdametinib. As of the 20 Sept 2023 data cutoff (DCO), BICR-confirmed ORR during the treatment phase was 41% (95% CI, 29-55; P<.001 vs null) in adults and 52% (95% CI, 38-65; P<.001 vs null) in pediatric pts. Two adult pts and 1 pediatric pt also had a confirmed response in the ongoing LTFU. Median (min, max) target PN volumetric best response from BL was -41% (-90, 13) and -42% (-91, 48) in adult and pediatric pts, respectively. As of the DCO, median treatment duration was 22 mo for each cohort and median DoR was not reached. Median (range) TTR was 7.8 (4-19) mo in adult pts and 7.9 (4-19) mo in pediatric pts. Adult and pediatric pts had statistically significant improvements from BL to cycle 13 in NRS-11, PII, and key PedsQL measures. Most frequent (≥35% pts) treatment-emergent adverse events (TEAEs) were dermatitis acneiform, diarrhea, nausea, and vomiting in adults and diarrhea, dermatitis acneiform, and vomiting in pediatric pts. 16% and 25% of adult and pediatric pts, respectively, had grade ≥3 treatment-related AEs, and 22% and 9%, respectively, discontinued due to TEAEs. Conclusions: In ReNeu, the largest multicenter NF1 PN trial reported to date, mirdametinib demonstrated a statistically significant ORR by BICR, with deep and durable PN volume reductions, significant improvements in pain severity, pain interference, and HRQoL, and a manageable safety profile in both adults and children. Together with a dispersible tablet formulation, these results underscore mirdametinib’s potential to become an important new treatment option for NF1 PN pts across all ages. Clinical trial information: NCT03962543 .