1013 Background: In the phase 3 ASCENT-04/KEYNOTE-D19 study (NCT05382286) SG + pembro showed significant and clinically meaningful progression-free survival (PFS) improvement vs chemo + pembro in pts with previously untreated PD-L1+ mTNBC. SG + pembro exhibited a manageable safety profile consistent with prior studies for each agent. We present preplanned exploratory efficacy analyses in ASCENT-04 by biomarker subgroups. Methods: 443 pts received (1:1 ratio) SG + pembro in 21-day cycles or chemo (gemcitabine + carboplatin; taxane) + pembro. From centrally tested fresh or archival tumor samples, Trop-2 expression was determined by immunohistochemistry (IHC), tumor BRCA (tBRCA) status by whole exome sequencing, and HER2 expression by in situ hybridization (ISH) + IHC. Pts were grouped by Trop-2 expression quartiles, tBRCA status (wild-type [WT] or mutant [mut] in BRCA1/BRCA2 /both), and HER2 status (IHC 0 vs Low [IHC 1+ or IHC 2+/ISH–]). Biomarker subgroups were analyzed descriptively for association with PFS by blinded independent central review (BICR); other outcomes by biomarker status are forthcoming. Results: Median Trop-2 H-score was 280, ranges: quartile 1 (Q1) 0-224, Q2 225-279, Q3 280-298, Q4 299-300. SG + pembro demonstrated longer PFS by BICR in Q3/Q4 vs Q1/Q2, and benefit was observed for SG + pembro vs chemo + pembro in all quartiles (Table). Hazard ratios (HR; 95% confidence interval [CI]) were: Q1, 0.81 (0.48-1.36); Q2, 0.73 (0.44-1.22); Q3, 0.46 (0.27-0.80); Q4, 0.57 (0.33-0.99). Proportion of pts with tBRCA mutations (~20%) was similar between treatment groups. Longer PFS was observed with SG + pembro with HR (95% CI) of 0.67 (0.49-0.91) in the tBRCA WT and 0.88 (0.45-1.74) in the tBRCA mut subgroups. PFS was longer with SG + pembro vs chemo + pembro in the HER2 IHC 0 and HER2 low subgroups, HR (95% CI) 0.69 (0.46-1.04) and 0.67 (0.48-0.92), respectively. Conclusions: SG + pembro demonstrated longer PFS vs chemo + pembro across all Trop-2, tBRCA, and HER2 subgroups. These analyses strengthen support for the significant, clinically meaningful benefit of SG + pembro as first-line treatment for mTNBC across subgroups. Clinical trial information: NCT05382286 . Efficacy, BICR N Median PFS (95% CI), mo Biomarker Subgroup SG + pembro Chemo + pembro SG + pembro Chemo + pembro HR (95% CI) Trop-2(n = 400) Q1 48 47 9.3(7.4-19.4) 9.0(6.0-10.9) 0.81(0.48-1.36) Q2 50 50 9.6(7.3-16.7) 7.4(6.9-9.7) 0.73(0.44-1.22) Q3 55 50 13.5(9.3-NR) 8.4(5.6-10.8) 0.46(0.27-0.80) Q4 51 49 16.6(8.1-NR) 9.2(5.5-11.3) 0.57(0.33-0.99) tBRCA(n = 332) WT 130 131 9.6(7.6-16.7) 7.4(6.9-9.2) 0.67(0.49-0.91) Mut 39 32 16.6(7.5-NR) 12.9(7.1-NR) 0.88(0.45-1.74) HER2(n = 435) IHC 0 84 82 16.6(9.1-21.2) 9.0(7.2-10.8) 0.69(0.46-1.04) Low 133 136 11.2(9.1-16.6) 7.7(7.0-9.4) 0.67(0.48-0.92)

LBA1000 Background: In ASCENT-04, first-line (1L) SG + pembro led to a statistically significant and clinically meaningful improvement in PFS vs chemo + pembro (median, 11.2 vs 7.8 mo; hazard ratio [HR], 0.65; 95% CI, 0.51-0.84; P < .001) in pts with previously untreated PD-L1+ mTNBC. Overall survival (OS) data are immature. PFS2 is more strongly associated with OS than PFS and can be used to measure long-term clinical benefit in the absence of mature OS data or when OS may be impacted by crossover. We report PFS2 and subs tx from ASCENT-04. Methods: Pts (N = 443) were randomized 1:1 to SG (10 mg/kg IV, days 1 & 8) + pembro (200 mg, day 1, max 35 cycles) in 21-day cycles or chemo (gemcitabine + carboplatin, paclitaxel, or nab-paclitaxel) + pembro; the primary end point was PFS by blinded independent central review (BICR). Eligible pts in the chemo + pembro group could receive 2L SG provided on study via crossover following BICR-verified progressive disease (PD) or in any subs line commercially; other subs txs per local practice were also permitted. PFS2 was defined as the time from randomization to first documented PD on next-line therapy per investigator assessment or death due to any cause, whichever occurred first. Results: Median follow-up for OS was 14.0 mo; 95 (43%) pts remained on study tx in the SG + pembro group (n = 221) and 52 (23%) in the chemo + pembro group (n = 222). Of the 125 pts in the SG + pembro group who discontinued tx, 69 received any subs tx, the most frequent of which were taxanes (42%), platinum chemo (33%), and capecitabine (33%). Of the 170 pts in the chemo + pembro group who discontinued tx, 119 received any subs tx, the most frequent of which were SG (81%), taxanes (9%), and capecitabine (9%). Median PFS2 and PFS2 rates are in the Table. Median (95% CI) time to first subs tx was 17.3 mo (12.7-not reached [NR]) for SG + pembro and 9.8 mo (8.7-10.9) for chemo + pembro; median (95% CI) time to second subs tx was NR (22.9 mo-NR) and 21.0 mo (16.6-NR). Conclusions: PFS2 was improved in the SG + pembro group vs chemo + pembro group despite crossover tx, with most pts who initiated subs tx in the chemo + pembro group receiving SG. In pts with previously untreated PD-L1+ mTNBC, SG + pembro provided clinically relevant continued benefit beyond first progression, further supporting SG + pembro as a potential new standard of care. Clinical trial information: NCT05382286 . SG + pembro Chemo + pembro Pts with PFS2 events, n/N (%) 55/221 (25) 83/222 (37) Median PFS2 (95% CI), mo NR (NR-NR) 21.0 (16.0-NR) Stratified HR a (95% CI) 0.67 (0.48-0.95) Stratified log-rank nominal P -value a .0224 PFS2 rate (95% CI), % 12 mo 80.0 (73.8-84.9) 75.7 (69.1-81.1) 18 mo 71.9 (64.5-78.0) 53.0 (44.5-60.8) 24 mo 63.7 (51.1-73.9) 45.6 (35.6-55.1) a SG + pembro vs chemo + pembro.

LBA109 Background: Although PD-1/PD-L1 inhibitors plus chemo have expanded treatment options for previously untreated PD-L1–positive advanced TNBC, there still remains a critical unmet need to improve outcomes. SG previously demonstrated significant clinical benefit in pretreated metastatic TNBC (mTNBC). We report results from the ASCENT-04/KEYNOTE-D19 study in patients with previously untreated, PD-L1–positive (CPS ≥ 10; 22C3 assay) locally advanced unresectable or mTNBC. Methods: Patients were randomized 1:1 to SG (10 mg/kg IV, day 1 & 8) + pembro (200 mg, day 1, max 35 cycles) in 21-day cycles or chemo (gemcitabine + carboplatin, paclitaxel, nab-paclitaxel) + pembro until disease progression or unacceptable toxicity. Randomization was stratified by curative treatment-free interval, geography, and prior exposure to anti–PD-(L)1 therapy in the curative setting. Primary endpoint was progression-free survival (PFS) by blinded independent central review (BICR). Key secondary endpoints include overall survival (OS); objective response rate (ORR) and duration of response (DOR) by BICR; and safety. Results: 443 patients were randomized at a 1:1 ratio: 221 to SG + pembro and 222 to chemo + pembro. The median follow-up was 14 mo. SG + pembro showed a significant improvement in PFS by BICR compared with chemo + pembro (hazard ratio [HR], 0.65; 95% CI, 0.51-0.84; P = .0009; Table). Median DOR was 16.5 mo for SG + pembro vs 9.2 mo for chemo + pembro (Table). Although OS data were immature, a positive early trend in OS improvement was also noted. The most frequent (≥ 10% of patients) grade ≥ 3 treatment-emergent adverse events (TEAEs) with SG + pembro were neutropenia (43%) and diarrhea (10%); and with chemo + pembro were neutropenia (45%), anemia (16%), and thrombocytopenia (14%). Conclusions: SG + pembro led to a statistically significant and clinically meaningful improvement in PFS vs chemo + pembro with durable responses, no new safety concerns for SG or pembro, and a lower rate of treatment discontinuation due to TEAEs in patients with previously untreated, PD-L1–positive advanced TNBC. These data support the use of SG + pembro as a potential new standard of care treatment in this patient population. Clinical trial information: NCT05382286 . Efficacy, BICR, intent-to-treat SG + pembro(n = 221) Chemo + pembro(n = 222) Median PFS (95% CI), mo 11.2 (9.3-16.7) 7.8 (7.3-9.3) HR (95% CI); P -value (adjusted for randomization stratification factors) 0.65 (0.51-0.84); P = .0009 ORR (95% CI), % 59.7 (52.9-66.3) 53.2 (46.4-59.9) Median DOR (95% CI), mo 16.5 (12.7-19.5) 9.2 (7.6-11.3) Safety (TEAEs), all treated, n (%) n = 221 n = 220 Any grade; grade ≥ 3 220 (> 99); 158 (71) 219 (> 99); 154 (70) Led to dose reduction 78 (35) 96 (44) Led to any treatment discontinuation 26 (12) 68 (31)

2551 Background: Adagloxad simolenin (AS) is a therapeutic cancer vaccine composed of Globo H linked to the carrier protein keyhole limpet hemocyanin. OBI-821 is an adjuvant administered with AS to strengthen immune response. This phase 3 trial assessed safety/efficacy of AS/OBI-821 in patients with triple negative breast cancer (TNBC; NCT03562637). Methods: Eligible patients for this randomized, open-label trial were adults with high-risk (≥1cm residual primary, ≥1 residual axillary node after neoadjuvant chemotherapy, or stage IIB or III cancer treated with adjuvant chemotherapy alone), primary localized early-stage, Globo H-positive (H-score ≥15) TNBC. Patients were required to have received ≥4 cycles of standard taxane- and anthracycline-based chemotherapy. Patients were randomized 1:1 to receive standard of care (SOC; observation alone [29%], capecitabine [69%], or a checkpoint inhibitor ± capecitabine [2%]) or AS/OBI-821 and SOC (observation alone [26.6%], capecitabine [69.6%], or a checkpoint inhibitor ± capecitabine [3.8%]). Patients in the AS/OBI-821 arm received 4 weekly doses of study drug administered via subcutaneous injection, followed by 4 biweekly doses, 4 doses every 4 weeks, then doses every 8 weeks up to 100 weeks. The primary endpoint was invasive disease-free survival (IDFS); secondary endpoints included safety assessed via treatment-emergent adverse events (TEAEs) and overall survival (OS). Patients were followed for up to 5 years after randomization for OS. Results: The intent-to-treat (ITT) population was comprised of 575 patients, with 286 in the AS/OBI-821 arm, and 289 in the SOC arm. Patients were a median age of 51 years (range 24-85), all were female, and most were white (52.7%). A total of 5.2% of patients had stage I cancer, 50.3% had stage II, and 37.1% had stage III. IDFS in the AS/OBI-821 arm was not statistically different than in the SOC arm (IDFS hazard ratio [HR], 1.23 [95% CI: 0.88, 1.73]; P = 0.23). Three-year IDFS rate was 54.5% for AS/OBI-821 arm and 56.4% for the SOC arm. Similar pattern was observed for OS with HR = 1.36 [95% CI: 0.77, 2.38). TEAEs occurred in 79.6% of patients in the AS/OBI-821 arm and 66.7% in the SOC arm. The most common TEAEs in the AS/OBI-821arm were palmar-plantar erythrodysaesthesia syndrome (18.7%), fatigue (11.6%), and headache (11.3%). Serious TEAEs occurred in 5.3% of patients in the AS/OBI-821 arm vs 6.2% in the SOC arm. One patient (0.4%) in the AS/OBI-821 arm had a TEAE of interstitial lung disease, assessed as unlikely related to treatment and one patient (0.3%) in the SOC arm had acute coronary syndrome that led to death. Conclusions: In this phase 3, randomized, open-label trial, AS/OBI-821 was well-tolerated, with a safety profile similar to SOC. IDFS and OS were similar between the AS/OBI-821 and SOC arms. The trial was terminated per recommendation by the Data and Safety Monitoring Board as it met prespecified futility criteria. Clinical trial information: NCT03562637 .

TPS9601 Background: Immune checkpoint inhibitors (ICIs), including anti-PD-1 antibodies, reverse tumor induced immune suppression and promote effective anti-tumor T-cell responses. They have drastically improved outcome in advanced melanoma therapy, yielding durable improvements in progression-free survival (PFS) and overall survival (OS). Although adding anti-CTLA-4 or anti-LAG-3 enhances efficacy beyond anti-PD-1 alone, these approaches do not directly target dominant myeloid-mediated resistance mechanisms within the tumor microenvironment, and new agents targeting this axis are needed. EIK1001, a TLR7/8 dual-agonist, activates myeloid and plasmacytoid dendritic cells to stimulate innate inflammation and adaptive immunity. Across multiple studies, EIK1001 has been well tolerated and has demonstrated clinical activity both as monotherapy and in combination with ICIs. Methods: TeLuRide-006 (NCT#06697301) is a global, multicenter, randomized, double-blind, adaptive Phase 2/3 trial of EIK1001 or placebo, in combination with pembrolizumab (pembro), as first-line therapy for participants (pts) with advanced cutaneous melanoma. Approximately 740 pts will be randomized, including a dose-optimization (DO) stage in which pts are randomized 1:1:1 to two EIK1001 dose levels or placebo, each administered with pembro, followed by Phase 2/3 expansion evaluating the selected EIK1001 dose versus placebo, with pembro. Interim analyses will guide progression from DO to Phase 2 and subsequently to Phase 3. EIK1001 or placebo is administered IV QW until the end of Week 27 then Q3W; while pembro is administered IV Q3W. Pts are stratified by prior anti-PD-1 adjuvant therapy, LDH level, and BRAF mutational status. Key eligibility criteria include patients ≥12 years (with country-specific variations), life expectancy ≥3 months, unresectable Stage III or Stage IV melanoma, known BRAF V600 status, at least one RECIST v1.1–measurable lesion, and no prior or current pneumonitis/interstitial lung disease. Primary objectives are to assess the efficacy and safety of two EIK1001 doses with pembro in DO, and to compare PFS (RECIST v1.1 by blinded independent central review [BICR]) and OS between the selected EIK1001 dose and placebo in combination with pembro. Secondary objectives include safety and tolerability of either EIK1001 dose with pembro, objective response rate and duration of response per RECIST v1.1 by BICR. Exploratory objectives include time to response, EIK1001 exposure-response relationships, and health-related quality of life. This study enrolled (randomized) its first participant on 5/21/2025 and is activated at 91 sites in 22 countries at the time of abstract submission.

This review is focused on understanding the reasons why basal cell carcinoma (BCC), the most common, increasingly prevalent cancer, is classified as an “immune excluded” malignancy. It is, despite manifesting one of the highest tumor mutational burdens of any solid human malignancy, considered to be a biomarker of enhanced tumor immunogenicity and efficacy of tumor-targeted immunotherapy. Following a brief clinical overview, the balance of the review addresses important translational issues based on recent insights into the mechanisms underpinning immune exclusion/evasion in BCC. These include, firstly, the role of infectious agents and non-infectious potential causes of predisposition for and/or exacerbation of disease development and progression. Secondly, an overview of existing and emerging novel therapeutic strategies to ameliorate immune exclusion in BCC based on targeting several key immunosuppressive mechanisms. These are (i) inappropriate activation of the hedgehog signaling pathway (HHSP) due to formation of key driver mutations; (ii) interference with the presentation of tumor-specific antigens/neoantigens to cytotoxic T-cells; (iii) attenuation of the influx of anti-tumor natural killer cells; (iv) the recruitment and activation of immune suppressive regulatory T-cells; and (v) localized and systemic immune dysfunction achieved via elevated levels of soluble co-inhibitory immune checkpoint proteins (ICPs). The final section is focused on current and emerging pharmacologic and immune-based therapies.

BACKGROUND:MK-3475A is pembrolizumab with berahyaluronidase alfa for subcutaneous administration (pembrolizumab SC). The phase 1 study 3475A-C18 (NCT05017012) assessed the pharmacokinetic and safety profiles of pembrolizumab SC. METHODS:The study had 4 arms that enrolled participants with unresectable or advanced melanoma (arms 1, 2, and 4), metastatic NSCLC (arms 1-3), or advanced or metastatic RCC (arms 1 and 2). Participants received pembrolizumab SC 650 mg Q6W at solution strengths of 165 mg/mL (arms 1 and 3), 130 mg/mL (arm 2), or pembrolizumab SC 395 mg Q3W at 165 mg/mL (arm 4). Key endpoints included pembrolizumab SC bioavailability, pharmacokinetics, immunogenicity, and safety and tolerability. RESULTS:140 participants received study treatment. Across all arms, mean bioavailability of pembrolizumab SC was 61 % (95 % CI, 58 %64 %; CV%, 22.4 %) and absorption rate was 0.30/day (95 % CI, 0.28-0.32/day; CV%, 43.7 %). Pharmacokinetic exposure, bioavailability, and absorption rate did not differ meaningfully with pembrolizumab SC by solution strength. Treatment-emergent anti-drug antibodies against pembrolizumab and berahyaluronidase occurred in 1 % and 2 % of participants, respectively. Injection site AEs with pembrolizumab SC occurred in 16 % of participants; all were grade 1/2 in severity. Immune-mediated AEs occurred in 41 % of participants in arms 1-3 and 18 % of participants in arm 4. CONCLUSION:Results from study 3475A-C18 informed selection of pembrolizumab SC 790 mg Q6W at 165 mg/mL for further clinical development to ensure that all patients have the appropriate pembrolizumab exposure to derive expected clinical benefit. Arm 4 results provided key clinical data supporting the pembrolizumab SC 395 mg Q3W dosing regimen. TRIAL REGISTRATION:ClinicalTrials.gov, NCT05017012.

Pembrolizumab is approved for use across multiple cancers at doses of 200 mg Q3W, 2 mg/kg Q3W, or 400 mg Q6W administered as an intravenous (IV) infusion. Alternative subcutaneous (SC) formulations can provide added convenience and flexibility in the clinic. MK-3475A is pembrolizumab with berahyaluronidase alfa (MK-5180), a variant of human hyaluronidase developed and manufactured by Alteogen Inc., for SC administration of pembrolizumab (hereafter referred to as “pembro SC”). The purpose of this arm of the phase 1, nonrandomized, multi-arm, open-label 3475A-C18 study is to generate the first clinical data for pembro SC administered Q3W, with PK exposure measures as the primary endpoint. PK data will be used to validate model-based predictions and confirm Q3W SC dosing regimen. In arm 4 of this phase 1 study (NCT05017012), adults with unresectable advanced melanoma received pembro SC 395 mg Q3W for up to 35 cycles. Using serum concentration data collected in cycles 1-6, the primary objective was to characterize the PK profile of pembro SC administered Q3W in cycle 1 and cycle 6 (steady state). Other objectives included the evaluation of anti-drug antibodies (ADA) against pembro SC (secondary), characterization of the safety and tolerability of pembro SC (secondary), and evaluation of the systemic concentrations of and ADA against MK-5180 (tertiary). 44 participants were treated with pembro SC 395 mg. Median (range) age was 60 years (30-89) and 50% were male. Median (range) pembro PK exposure measures in cycle 1 and at steady state were: Cmax 34.1 µg/mL (10.6-63.7) and 80.7 µg/mL (30.9-162); Ctrough 21.1 µg/mL (9.7-40.5) and 54.6 µg/mL (21.7-123); AUC0-3wks 567 µg·day/mL (192-979) and 1446 µg·day/mL (604-3050); Tmax 5 days (2-10) and 4 days (2-8). ADAs against pembro were detected in 1 of 40 (3%) evaluable participants, with no effect on pembro exposure observed. No samples had detectable MK-5180 levels, and ADAs against MK-5180 were not detected. On physical exam, 9 (20.5%) participants had injection site AEs, most frequently erythema (n=4) and injection site reaction (n=2). All injection site reactions were nonserious, grade 1, and effectively managed. Eight (18%) participants had an immune-mediated AE, most commonly hypothyroidism (n=3, 7%). The PK exposures of pembro SC Q3W in this study were generally consistent with model-based predictions and with PK exposures for pembro SC 790 mg Q6W and pembro IV 200 mg Q3W dosing regimens, thereby validating the model and confirming 395 mg Q3W as a dosing regimen for pembro SC. The overall systemic safety profile of pembro SC Q3W was consistent with the known safety profile of pembrolizumab monotherapy. Corlia Coetzee, Richard Khanyile, Graham Cohen, Georgina McAdam, Cathryn Walton, Sze Wai Chan, Bernardo Rapoport, Christian Caglevic, Patricio Yañez, Mallika Lala, Gina Song, Julia W. Cohen, Carlos Rojas. Pharmacokinetics (PK), safety, and tolerability of pembrolizumab with berahyaluronidase alfa administered subcutaneously Q3W in participants with advanced melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_2):Abstract nr CT035.

TPS9604 Background: Immune checkpoint inhibitors (ICIs) relieve immunosuppression of tumor-reactive T cells and enhance antitumor response. Significant advances for the treatment of advanced melanoma have been made using ICIs, with overall survival (OS) benefit conferred by ICI monotherapy. While encouraging results have been observed with combinations of ICIs, no α-controlled, statistically significant OS benefit of combinations over monotherapy has been demonstrated in Phase 3 studies. Despite these advances, 5-year survival for advanced disease is only 15 to 20%, motivating development of new therapies. EIK1001 is a TLR7/8 agonist that stimulates myeloid and plasmacytoid dendritic cells, activating immune and inflammatory responses. This dual activity, distinct from effects on checkpoint proteins, enhances antitumor T-cell activity alone or in combination with ICIs. Methods: TeLuRide-006 (NCT#06697301) is a global, multicenter, randomized, double-blind, adaptive Phase 2/3 study of EIK1001 or placebo in combination with pembrolizumab (pembro) as first-line therapy in participants (pts) with advanced melanoma. This study includes dose-optimization (DO), in which pts are randomized 1:1:1 to receive 1 of 2 doses of EIK1001 or placebo in combination with pembro, followed by adaptive Phase 2/3 expansion at the Selected Dose of EIK1001 + pembro or placebo + pembro. Interim analyses will determine whether the study advances from DO to Phase 2 to Phase 3. EIK1001 or placebo is administered intravenously QW until the end of Week 27 then Q3W. Pts are stratified by prior anti-PD-1 adjuvant therapy, LDH level, and BRAF mutational status. Key eligibility criteria: pts ≥ 18 years of age with a life expectancy of ≥ 3 months, Stage 3 (unresectable) or Stage 4 metastatic melanoma, known BRAF V600 mutational status (or consent to BRAF mutation testing), ≥ 1 measurable lesion by RECIST v1.1, and no history of or current pneumonitis/interstitial lung disease. Primary objectives are to evaluate the efficacy and safety of 2 doses of EIK1001 in combination with pembro (DO only) and to compare progression-free survival per RECIST 1.1 by blinded independent central review (BICR) and OS of pts receiving EIK1001 + pembro relative to pts receiving placebo + pembro (at Selected Dose). Secondary objectives include evaluation of the safety and tolerability of the Selected Dose of EIK1001 + pembro relative to placebo + pembro, as well as evaluation of objective response rate and duration of response per RECIST 1.1 by BICR. Exploratory objectives include evaluation of time to objective response, evaluation of potential EIK1001 exposure-response relationships, and evaluation of health-related quality of life, health utilities, and melanoma concerns in pts receiving EIK1001 + pembro relative to placebo + pembro. This study opened on 24 December 2024. Clinical trial information: 06697301 .

Recent advances in the field of immuno-oncology have brought transformative changes in the management of cancer patients. The immune profile of tumours has been found to have key value in predicting disease prognosis and treatment response in various cancers. Multiplex immunohistochemistry and immunofluorescence have emerged as potent tools for the simultaneous detection of multiple protein biomarkers in a single tissue section, thereby expanding opportunities for molecular and immune profiling while preserving tissue samples. By establishing the phenotype of individual tumour cells when distributed within a mixed cell population, the identification of clinically relevant biomarkers with high-throughput multiplex immunophenotyping of tumour samples has great potential to guide appropriate treatment choices. Moreover, the emergence of novel multi-marker imaging approaches can now provide unprecedented insights into the tumour microenvironment, including the potential interplay between various cell types. However, there are significant challenges to widespread integration of these technologies in daily research and clinical practice. This review addresses the challenges and potential solutions within a structured framework of action from a regulatory and clinical trial perspective. New developments within the field of immunophenotyping using multiplexed tissue imaging platforms and associated digital pathology are also described, with a specific focus on translational implications across different subtypes of cancer. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

The current study compared the levels and possible associations between systemic soluble immune checkpoints (sICPs, n = 17) and a group of humoral modulators of immune suppressor cells (n = 7) in a cohort of patients with basal cell carcinoma (BCC, n = 40) and a group of healthy control subjects (n = 20).The seven humoral modulators of immunosuppressor cells were represented by the enzymes, arginase 1 and fibroblast activation protein (FAP), the chemokine, RANTES (CCL5) and the cytokines, interleukin-10 and transforming growth factor-β1 (TGF-β1), as well as the M2-type macrophage markers, soluble CD163 (sCD163) and sCD206.The plasma levels of six co-inhibitory sICPs, sCTLA-4, sLAG-3, sPD-1, sPD-L1, sTIM-3 and sPD-L2 were significantly elevated in the cohort of BCC patients (p<0.001-p<0.00001), while that of sBTLA was significantly decreased (p<0.006). Of the co-stimulatory sICPs, sCD27 and sGITR were significantly increased (p<0.0002 and p<0.0538) in the cohort of BCC patients, while the others were essentially comparable with those of the control participants; of the dual active sICPs, sHVEM was significantly elevated (p<0.00001) and TLR2 comparable with the control group. A correlation heat map revealed selective, strong associations of TGF-β1 with seven co-stimulatory (z = 0.618468–0.768131) and four co-inhibitory (z = 0.674040–0.808365) sICPs, as well as with sTLR2 (z = 0.696431).Notwithstanding the association of BCC with selective elevations in the levels of a large group of co-inhibitory sICPs, our novel findings also imply the probable involvement of TGF-β1 in driving immunosuppression in this malignancy, possibly via activation of regulatory T cells. Notably, these abnormalities were present in patients with either newly diagnosed or recurrent disease.

3040 Background: Cells of the immune system and malignant cells interact in the tumor microenvironment, influencing response to treatment and survival. The current study was undertaken to assess the prevalence of these immune cells systemically in patients with early triple-negative breast cancer (TNBC). Methods: Multi-parameter flow cytometry was used to examine the percentages and phenotypes of cytotoxic T cells, natural killer (NK) cells, monocyte subsets, and regulatory T cell (Treg) subsets in the peripheral blood of 19 TNBC patients (pts) and 10 controls (cnt). Multicolor flow cytometry was carried out using DURAClone IM phenotyping (basic and Treg tubes) with a CytoFLEX Flow Cytometer (Beckman Coulter, California, USA), and data analyzed with FlowJo v 10.10.0 software (BD Life Sciences, USA). The Mann-Whitney U-test was used to compare non-parametric data where appropriate. Results: Significant increases in the percentages of immunosuppressive CD3+ CD4+ CD39+ Tregs cells in the setting of a significant decrease of CD19+ B cells were observed in pts with TNBC (Table).Tumour size, nodal status, age and ki-67 did not correlate with the percentages of any type of circulating immune cell. Conclusions: TNBC is associated with severe immunosuppression. In this context, percentages of circulating CD19+ B cells were significantly lower, while CD3+ CD4+ CD39+ Tregs were significantly higher in early TNBC pts. The peripheral blood immunome of TNBC pts identified a subset of immunosuppressive Tregs. A study is ongoing to identify the prognostic and predictive values of this systemic subset of Tregs for pCR in early TNBC pts undergoing neoadjuvant chemotherapy. [Table: see text]

Purpose Review the literature to update the MASCC guidelines from 2016 for controlling nausea and vomiting with systemic cancer treatment of low and minimal emetic potential. Methods A working group performed a systematic literature review using Medline, Embase, and Scopus databases between June 2015 and January 2023 of the management of antiemetic prophylaxis for anticancer therapy of low or minimal emetic potential. A consensus committee reviewed recommendations and required a consensus of 67% or greater and a change in outcome of at least 10%. Results Of 293 papers identified, 15 had information about managing systemic cancer treatment regimens of low or minimal emetic potential and/or compliance with previous management recommendations. No new evidence was reported that would change the current MASCC recommendations. No antiemetic prophylaxis is recommended for minimal emetic potential therapy, and single agents recommended for low emetic potential chemotherapy for acute emesis, but no prophylaxis is recommended for delayed emesis. Commonly, rescue medication includes antiemetics prescribed for the next higher level of emesis. Conclusion There is insufficient data to change the current guidelines. Future studies should seek to more accurately determine the risk of emesis with LEC beyond the emetogenicity of the chemotherapy to include patient-related risk assessment.

Intravenous pembrolizumab 400 mg every 6 weeks was approved across tumor types based on pharmacokinetic modeling, which showed exposures consistent with previous standard dosing of 200 mg or 2 mg/kg every 3 weeks, and early results of cohort B of the phase 1 KEYNOTE-555 study. Results after ≥1 year of potential follow-up for all patients in cohort B of KEYNOTE-555 are presented. Patients aged ≥18 years with previously untreated stage III/IV melanoma received pembrolizumab 400 mg every 6 weeks for ≤18 cycles. The primary endpoint was objective response rate per RECIST v1.1 by blinded independent central review. Secondary endpoints included duration of response, progression-free survival, pharmacokinetics, and safety. Overall, 101 patients received pembrolizumab. Median projected follow-up was 21.9 months (range, 17.0-25.7). The objective response rate was 50.5% (95% CI: 40.4-60.6; 19 complete responses, 32 partial responses). Median duration of response was not reached (NR; range, 2.4+ to 21.0+ months). Median progression-free survival was 13.8 months (95% CI: 4.1-NR). Observed pharmacokinetic exposures were consistent with model predictions for pembrolizumab 400 mg every 6 weeks and other approved and tested schedules (2 mg/kg or 200 mg every 3 weeks). Grade 3-4 treatment-related adverse events occurred in 13 patients (12.9%). No deaths were considered treatment related. These results support the pharmacokinetic modeling and demonstrate that the benefit-risk profile of pembrolizumab 400 mg Q6W is consistent with that of 200 mg or 2 mg/kg every 3 weeks. Clinically meaningful objective response rate and durable progression-free survival within the expected range for first-line pembrolizumab were observed. Clinical trial registry: ClinicalTrials.gov, NCT03665597.

Filgrastim is approved for several indications, including reduction of the incidence and duration of chemotherapy-induced neutropenia and for stem cell mobilization. The filgrastim biosimilar, EP2006, has been available in Europe since 2009, and in the United States since 2015. In this time, preclinical and clinical data used to support the approval of EP2006 have been published. These data established the biosimilarity of EP2006 to reference filgrastim in terms of structure, pharmacokinetics, pharmacodynamics, efficacy, safety, and immunogenicity. Additional real-world evidence studies have also demonstrated equivalent efficacy and safety of EP2006 compared with reference filgrastim, both in the reduction of neutropenia and in stem cell mobilization in clinical practice. This review summarizes these preclinical, clinical, and real-world data, as well as the available cost-effectiveness data, for EP2006 since its approval 15 years ago.

Quality of life (QoL), appetite, cachexia, and biomarkers [albumin, hemoglobin (Hb), neutrophils, lymphocytes, platelets, C-reactive protein (CRP), tumor necrosis factor alpha (TNFα), interleukin 6 (IL-6), interleukin 8 (IL-8), C-X-C motif chemokine ligand 5 (CXCL5) and citrullinated histoneH3 (H3Cit)] were compared for 40 cases with advanced cancer and 40 healthy controls. Baseline differences and significant relationships were explored for biomarkers with QoL, appetite, and cachexia. In a prospective case–control, age and sex matched study, the European Organisation for the Research and Treatment of Cancer Quality of Life–C30 questionnaire (EORTC-QLQ-C30) for QoL, the Functional Assessment of Anorexia and Cachexia Therapy assessment (FAACT A/CS-12) for appetite, and a five-factor cachexia assessment tool for cachexia assessment were performed. Routine hematological measurements and blood chemistry analyses together with ELISA procedures and a Multiplex® bead array platform, were used for biomarker analysis. Descriptive statistics and regression analyses were undertaken. P < 0.05 defined statistical significance. Global health status (QL-G), functional scales (QL-FS), and symptom scales (QL-SS) differed for cases and controls (p < 0.01). In cases, differences were observed for QL-G (p < 0.01), QL-FS (p < 0.01), and QL-SS (p = 0.01) compared to standardized references values. FAACT A/CS-12 scores differed significantly between cases and controls (p < 0.01) and 30

PURPOSE:This paper aims to provide a comprehensive understanding of the need for continued development of symptom monitoring (SM) implementation, utilization, and data usage at the macro-, meso-, and micro-levels.METHODS:Discussions from a patient-reported SM workshop at the MASCC/ISSO 2022 annual meeting were analyzed using a macro-meso-micro analytical framework of cancer care delivery. The workshop categories "initiation and implementation, barriers to adoption and utilization, and data usage" were integrated for each level.RESULTS:At the macro-level, policy development could encourage data sharing and international collaboration, including the exchange of SM methods, supportive care models, and self-management modules. At the meso-level, institutions should adjust clinical workflow and service delivery and promote a thorough technical and clinical integration of SM. At the micro-level, SM should be individualized, with timely feedback for patients, and should foster trust and understanding of AI decision support tools amongst clinicians to improve supportive care.CONCLUSIONS:The workshop reached a consensus among international experts on providing guidance on SM implementation, utilization, and (big) data usage pathways in cancer survivors across the cancer continuum and on macro-meso-micro levels.

Breast cancer (BC) cells exploit the up-regulation or down-regulation of immune checkpoint molecules (ICM) to evade anti-tumor immune responses.ICMs can be measured in human plasma; however, their biological and clinical significance remains essentially unknown. The present analysis aimed to measure plasma ICMs in metastatic BC patients (pts) and compare them to healthy controls. Soluble forms of ICM and RANTES, arginase, TGF-b1, CD163, and CD206 were measured using Multiplex® bead array and ELISA technologies. Plasma samples from 20 metastatic breast cancer (MBC) pts and 45 healthy controls were analyzed for each protein, and compared between MBC pts and healthy controls using a non-parametric test (Mann-Whitney). The median age of the cohort was 53 years (range 34-79 years). The performance status was as follows; PS=0 (11 pts), PS=1 (7 pts) and PS=2 (2 pts). The soluble co-stimulatory molecules, GITR (p<0.0011), GITRL (p< 0.0000), CD27 (p< 0.0039), CD28 (p<0.0069), CD40 (p< 0.0022), CD86 (p< 0.0000) and ICOS (p< 0.0157), as well as the co-inhibitory molecules, PD-L1 (p< 0.0002), CTLA-4 (p< 0.0002) and BTLA (p<0.0145) levels were significantly lower in MBC pts compared to healthy controls. Conversely, the co-inhibitory molecules, TIM-3 (p< 0.0001) and LAG-3 (p<0.0000 were significantly higher than those of healthy controls. Other biomarkers with raised plasma concentrations included TLR (p<0.0039). Plasma CD80 (p<0.0992), PD-1 (p<0.2325), HVEM (p<0.062,6), RANTES (p<0.4861) CD163 (p<0,8565) and CD206 (p<0,2454) levels were not significantly different between the MBC pts and the healthy controls. We identified lower levels of CD27, CD28, CD40, ICOS, GITR, GITRL, CD86, PD-L1, CTLA-4, BTLA, arginase, and TGF-β1, and higher levels of TIM-3 and LAG-3 immune checkpoint molecules in MBC pts compared to healthy controls. These results indicate that a down-regulation of soluble ICM pathways and an up-regulation of some inhibitory ICM pathways are associated with MBC patients. To our knowledge, this is the first study to describe soluble immune checkpoint molecules in MBC pts.