Buckle, Geoffrey Colin

1510 Background: The National Comprehensive Cancer Network (NCCN) Harmonized Guidelines for Sub-Saharan Africa (SSA) have emerged as leading cancer treatment guidelines in SSA. The NCCN-SSA guidelines, derived by adapting NCCN guidelines for the SSA context, offer standardized recommendations to guide cancer care and shape policy in SSA. This study examines the evidence cited in support of the NCCN-SSA guidelines, with a focus on population characteristics and generalizability to SSA. Methods: Two reviewers independently examined the NCCN-SSA guidelines for the eight most common cancers in SSA to identify all studies cited in support of treatment/management recommendations. Study selection discrepancies were resolved by discussion. Full-text articles were reviewed and data on age, sex, race, and recruitment geography were abstracted. Descriptive analyses were performed using R statistical software. Results: Overall, 4,589 citations were reviewed, and 2,938 (64.0%) studies with individual-level data were included, representing >10.4 million study participants. Of the 2,061 studies reporting geographic information (70%), 50 (2.4%) recruited in SSA; of these, 39 (83.0%) recruited from South Africa. Three studies (0.2%) recruited exclusively in SSA. Most studies (95.3%) recruited exclusively from high or upper-middle income countries. Only 29.2% of studies with race data included >10% Black study participants. Conclusions: Most studies cited in the NCCN-SSA guidelines were conducted in high-income countries outside SSA. A small minority of all study participants were Black. Our findings underscore potential limitations in the generalizability of the NCCN-SSA guidelines to SSA and highlight a pressing need to generate and incorporate context-specific data to guide care and inform policy. WHO region of recruitment, race, and country-level income of studies included in NCCN-SSA guidelines. Cancer type # (%) studies reporting geography # (%) studies by recruitment region*: Americas # (%) studies by recruitment region*: Europe # (%) studies by recruitment region*: Sub-Sah. Africa % participants, White % participants, Black % participants, Other race # (%) studies representing only HMIC (per World Bank) Overall 2061(70%) 1177 (57%) 921 (45%) 50 (2%) 79% 9% 11% 1964(95%) B-cell 325(57%) 173 (53%) 178 (55%) 5(2%) 82% 7% 10% 307(94%) Breast 206(44%) 123 (60%) 124 (60%) 12 (6%) 80% 9% 11% 179(87%) Cervical 163(90%) 100 (61 %) 44(27%) 3(2%) 64% 14% 22% 158(97%) Colorectal 584(82%) 278 (48%) 292 (50%) 11 (2%) 80% 10% 10% 571 (98%) Hepato-cellular 183(74%) 80(44%) 68(37%) 0(0%) 69% 9% 22% 169(92 %) Kaposi sarcoma 51(80%) 25 (49%) 19(37%) 5(10%) 38% 51% 10% 44(86%) Ovarian 115(56%) 76 (66%) 35 (30%) 0(0%) 83% 4% 13% 115(100%) Prostate 434(88 %) 322 (74 %) 161 (37%) 14 (3%) 79% 9% 12% 421(97%) HMIC = high and upper-middle income countries. *Percent of studies includes as the denominator only the number of studies with reported geographies.

1015 Background: T-DXd is an antibody-drug conjugate approved for advanced HER2+/low/ultra-low breast cancer and multiple other solid tumors. T-DXd carries a rare but serious risk of ILD (incidence 12-15%), requiring frequent imaging and symptom evaluation. For > grade (G) 2 ILD, guidelines recommend permanent drug discontinuation. For asymptomatic G1 ILD, drug is held with the option for rechallenge (RC) if imaging findings resolve. Limited data exist on outcomes of RC after ILD in diverse real-world patients (pts). Methods: In this multi-center retrospective study, we analyzed pts with T-DXd related ILD treated from 2017-2024. Pts with ILD were identified via chart/ICD code review. Adjudication of T-DXd related ILD was based on treating providers’ assessment and graded via CTCAE v5. We collected pt demographics, T-DXd and steroid dosing, imaging results, and outcomes after RC. Statistical analysis was performed using Wilcoxon rank sum and Fisher’s exact tests. Results: Four centers treated 712 pts with T-DXd, with a 9.1% rate of any grade ILD (n=65). One other center reported only RC data in 18 pts with ILD. In total, 47 pts were RC; 38 after G1 ILD (81%), 9 after G2. Median (med) time to initial ILD was 145 days (d) after 1st dose (interquartile range [IQR] 78-205). Demographics for pts RC are shown in the table. Among 50 pts with G1 ILD, including pts not RC, 28/50 (56%) received steroids for a med of 36d (IQR 27-79). Radiographic improvement was seen at a med of 24d (IQR 19-63) for pts treated with steroids vs 82d (IQR 48-94) without (p<0.01); and a med of 35d (IQR 22-82) for pts RC vs 81d (IQR 68-105) for pts not RC (p=0.01). Among pts with G1 ILD, 38/50 (76%) were RC at a med of 42d (IQR 36-57) from last dose; 23/38 (61%) were dose reduced. After RC, pts remained on T-DXd for a med of 215d (IQR 60-334); 10/38 (26%) developed recurrent ILD (7-G1, 2-G2, 1-G3) at a med of 211d (IQR 47-273) from RC. No statistically significant differences were seen between ILD onset, time to RC, or demographics for pts with recurrent ILD vs not. Of the 9 pts RC after G2 ILD, T-DXd was continued for a med of 129d (IQR 49-171); 2/9 (22%) developed recurrent ILD (1-G2, 1-G3). No G5 toxicity was seen with RC. Conclusions: In this multi-center study, high RC rates were seen after G1 ILD with long duration of clinical benefit. Pts treated with steroids had faster radiographic ILD improvement, highlighting the importance of early steroid use. Among pts RC after G1 ILD, recurrent ILD rates were low, with the majority G1 and no G5 events. Notably, 9 pts with G2 ILD were RC, with a similar rate of recurrent ILD; this must be interpreted cautiously. Our large cohort data further supports the safety of T-DXd RC in diverse real-world settings. RC Pt Characteristics (n=47) n (%) or Median (IQR) Cancer typeBreastGIGyn 43 (91)3 (6)1 (2) Age (yrs) 57 (52-68) Prior # therapy lines in the advanced/metastatic setting 3 (1-5) Renal impairment (CrCl < 60 mL/min) 8 (17)

PURPOSE The eastern corridor of Africa is affected by a high burden of esophageal cancer (EC), with > 90% of patients presenting with advanced disease. Self-expanding metal stents (SEMS) have been previously reported as safe and effective for palliation of malignant dysphagia in resource-limited settings; however, access is limited throughout Eastern Africa. METHODS In response to demand for palliative interventions for patients with dysphagia because of EC, the African Esophageal Cancer Consortium (AfrECC) partnered with the Clinton Health Access Initiative to improve access to SEMS in Eastern Africa. We undertook a stepwise implementation approach to (1) identify barriers to SEMS access, (2) conduct a market analysis, (3) select an industry partner, (4) establish regulatory and procurement processes, (5) develop endoscopic training resources, (6) create a medical device registry, and (7) establish principles of accountability. RESULTS Following an evaluation of market demand and potential SEMS manufacturers, Boston Scientific Corporation announced its commitment to launch an access program to provide esophageal SEMS to patients in Tanzania, Kenya, Malawi, and Zambia at a subsidized price. Parallel regulatory and procurement processes were established in each participating country. Endoscopy training courses were designed and conducted, using the Training-of-Trainers model. A device registry was created to centralize data for quality control and to monitor channels of SEMS distribution. Principles of accountability were developed to guide the sustainability of this endeavor. CONCLUSION The AfrECC Stent Access Initiative is an example of a multisector partnership formed to provide an innovative solution to align regional needs with a supply chain for a high-priority medical device.