Gastrin-releasing peptide receptor (GRPR), overexpressed in many solid tumors, is a promising imaging marker and therapeutic target. Most reported GRPR-targeted radioligands contain a C-terminal amide. Based on the reported potent antagonist D-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHOH, we synthesized C-terminal hydroxamate-derived [68Ga]Ga-LW02075 ([68Ga]Ga-DOTA-pABzA-DIG-D-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHOH) and [68Ga]Ga-LW02050 ([68Ga]Ga-DOTA-Pip-D-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHOH), and compared them with the closely related and clinically validated [68Ga]Ga-SB3 ([68Ga]Ga-DOTA-pABzA-DIG-D-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHEt). Binding affinities (Ki) of Ga-SB3, Ga-LW02075, and Ga-LW02050 were 1.20 ± 0.31, 1.39 ± 0.54, and 8.53 ± 1.52 nM, respectively. Both Ga-LW02075 and Ga-LW02050 were confirmed to be GRPR antagonists by calcium release assay. Imaging studies showed that PC-3 prostate cancer tumor xenografts were clearly visualized at 1 h post injection by [68Ga]Ga-SB3 and [68Ga]Ga-LW02050 in PET images, but not by [68Ga]Ga-LW02075. Ex vivo biodistribution studies conducted at 1 h post injection showed that the tumor uptake of [68Ga]Ga-LW02050 was comparable to that of [68Ga]Ga-SB3 (5.38 ± 1.00 vs. 6.98 ± 1.36 %ID/g), followed by [68Ga]Ga-LW02075 (3.97 ± 1.71 %ID/g). [68Ga]Ga-SB3 had the highest pancreas uptake (37.3 ± 6.90 %ID/g) followed by [68Ga]Ga-LW02075 (17.8 ± 5.24 %ID/g), while the pancreas uptake of [68Ga]Ga-LW02050 was only 0.53 ± 0.11 %ID/g. Our data suggest that [68Ga]Ga-LW02050 is a promising PET tracer for detecting GRPR-expressing cancer lesions.

BACKGROUND: SB3 is a trastuzumab biosimilar approved in Australia, Brazil, Canada, the European Union, the Republic of Korea, Switzerland, and the USA. This real-world study evaluated safety and effectiveness of SB3 as part of the Korean post approval safety management system.
METHODS: This post-marketing surveillance in Korea included patients in line with approved indications, i.e., patients with early or metastatic breast cancer or metastatic gastric cancer. Safety outcomes were adverse events (AEs) and adverse drug reactions. Effectiveness outcomes were tumor response and event-free survival.
RESULTS: 424 patients were evaluated: 366 patients (86%) with early breast cancer, 53 patients (13%) with metastatic breast cancer, and 5 patients (1%) with metastatic gastric cancer. Among patients with breast cancer, AEs (mostly mild) and adverse drug reactions were reported by 158 (37.7%) and 57 (13.6%) patients, respectively. Most patients with an AE (141, 89.2%) had no change in treatment schedule. Treatment was temporarily suspended in 14 (8.9%) patients with an AE and completely discontinued in 7 (4.4%). Among patients with early and metastatic breast cancer who were evaluated for efficacy, objective response rates were 82.7% and 38.3%, respectively. Pathological complete response was 64.6% in patients with early breast cancer.
CONCLUSIONS: Safety and efficacy of SB3 demonstrated in this real-world study were comparable with previous studies of reference trastuzumab.

BACKGROUND: Dual blockade with trastuzumab and pertuzumab combined with neoadjuvant chemotherapy (NACT) has been increasingly used for HER2-positive tumours >2 cm and/or with positive axillary lymph nodes in order to evaluate pathologic response and obtain better surgical management. SB3 is a registered biosimilar trastuzumab approved following a phase III trial demonstrating similar efficacy in the neoadjuvant setting as trastuzumab. However, the study was done without pertuzumab.
METHODS: The database of the Danish Breast Cancer Group was used to extract data on all patients who started NACT with SB3 and pertuzumab between September 1, 2018 and August 31, 2019. The primary endpoint was pathological complete response (pCR) rate.
RESULTS: In total 215 patients received NACT and dual blockade. The median age was 55 (24-81). NACT used was cyclophosphamide and epirubicin followed by weekly paclitaxel (62% on six cycles, 35% on eight cycles) or other chemotherapy followed by weekly paclitaxel (3%). Overall, 56% of patients achieved pCR. 60 of 88 node-positive patients pre-NACT achieved ypN0(i-) after neoadjuvant treatment. pCR rate was significantly associated with estrogen receptor status and malignancy grade. An association with CEP17/HER2-ratio was assessed.
CONCLUSIONS: Real world data on dual blockade with SB3 and pertuzumab in combination with NACT in a nationwide population-based study show a pCR rate comparable to that seen in previous clinical studies.

The utilization of trastuzumab biosimilar medications is of particular interest in HER2-positive breast cancer as these drugs have the potential for cost savings and increased utilization/access to HER2 targeted therapy in both early stage and metastatic HER2-positive breast cancers. Five trastuzumab biosimilars: MYL-1401O (Ogivri), CT-P6 (Herzuma), SB3 (Ontruzant), PF-05280014 (Trazimera), and ABP980 (Kanjinti), have now been approved by the US Food and Drug Administration (FDA) for use in HER2-positive breast cancers. This review provides an overview of these agents with special consideration of the development and approval process, including available clinical data results for these trastuzumab biosimilars. Adoption in the clinic will depend on the degree of comfort with the overall evidence.

We assessed long-term cardiac safety and efficacy in patients with human epidermal growth factor receptor 2-positive early breast cancer treated with a trastuzumab biosimilar (SB3) or its reference product, trastuzumab (TRZ), in a phase 3 study.
Patients who completed the phase 3 study could be enrolled in this extension study. The outcomes included the incidence of symptomatic congestive heart failure (CHF), asymptomatic significant left ventricular ejection fraction (LVEF) decrease, incidence of other cardiac events, event-free survival (EFS), and overall survival. In post hoc analysis, the Cox proportional hazards regression model was used to assess factors associated with EFS.
A total of 367 patients were enrolled in the study (SB3, n = 186; TRZ, n = 181). The median follow-up duration from the main study enrolment was 40.8 and 40.5 months for SB3 and TRZ, respectively. During the two-year follow-up after adjuvant therapy, incidence of asymptomatic significant LVEF decrease was rare (SB3, n = 1; TRZ, n = 2), with all patients recovering with LVEF ≥ 50%, and no cases of symptomatic CHF or other cardiac events were reported. At 3 years, the EFS was 91.9% with SB3 and 85.2% with TRZ. The number of patients with events was 17 (9.1%) with SB3 and 31 (17.1%) with TRZ [hazard ratio: 0.47, 95% confidence interval: 0.26-0.87]. Antibody-dependent cell-mediated cytotoxicity (ADCC) activity and the breast pathologic complete response rate were the factors associated with EFS.
Cardiotoxicity was rare in this extension study. EFS was higher with SB3 versus TRZ, with post hoc analysis suggesting that a downward drift in ADCC activity was a contributing factor.
NCT02771795 (EudraCT 2015-005663-17).

Biosimilars are biologic products that are highly similar to, and have no clinically meaningful differences from, the approved originator molecule. They are poised to play an increasingly central role in cancer treatment, helping to improve access by driving down costs. Regulatory bodies have set out robust mechanisms for the approval of biosimilars, based on comprehensive and rigorous analytical and nonclinical comparisons with the originator. Product attributes (e.g., post-translational modifications) that are important to the function of the molecule must be similar between biosimilar and originator. This should be followed by a robust clinical development program, assessing pharmacokinetics, pharmacodynamics, efficacy, safety and immunogenicity. Equivalence in one indication might allow extrapolation across all the indications of the originator biologic. The recent approval of several trastuzumab biosimilars provides an example of how this process can work in practice for the benefit of patients, clinicians and payers.

Stability information for the trastuzumab biosimilar SB3 is limited to 48 h at 2-8 °C for the reconstituted solution and 24 h at up to 30 °C for diluted solutions. Extended physicochemical stability and biological activity were assessed to evaluate the advanced preparation of reconstituted and diluted SB3.
Under controlled and aseptic conditions, the stability of reconstituted and diluted SB3 was evaluated using several assessments and according to the UK\'s National Health Service guidance. Reconstituted SB3 was stored at 25 ± 2 °C with 60 ± 5% relative humidity for 3 days, and subsequently diluted SB3 (0.32-4 mg/mL) was stored in an infusion bag in the absence of light at 25 ± 2 °C with 60 ± 5% relative humidity for 28 days and 5 ± 3 °C for 28 days, respectively. Physicochemical stability (appearance, pH, protein concentration, size exclusion high-performance liquid chromatography, non-reducing capillary electrophoresis-sodium dodecyl sulfate, imaged capillary isoelectric focusing), biological activity (competitive inhibition binding assay to human epidermal growth factor receptor 2 by fluorescence resonance energy transfer, anti-proliferation assay), and properties with a potential safety impact (subvisible particulates, submicronic aggregation by dynamic light scattering) were determined.
No physicochemical instability signs or biological activity changes were observed for either reconstituted or diluted SB3 up to 28 days; all stability acceptance criteria were met. No major change was noted in the proportion of molecular weight variants (high molecular weight impurity, total purity) or relative percentages of acidic, main, and basic charge isoforms of the protein. No increases in particulates or aggregates in terms of a potential safety impact were noted.
The physicochemical stability and biological activity of reconstituted and diluted SB3 are maintained for extended time periods beyond those denoted in the product labeling, which allows for advanced SB3 preparation and may reduce drug wastage and preparation time.
Samsung Bioepis Co., Ltd.

BACKGROUND: Capsule endoscopy (CE) allows for a non-invasive small bowel evaluation for a wide range of gastrointestinal (GI) symptoms and diseases. Capsule technology has been rapidly advancing over recent years, often improving image frequency and quality. The Pillcam® SB3 (SB3) capsule is one such technology that offers an adaptive frame rate advantage over the previous versions of the capsule the Pillcam® SB2 (SB2). Some have proposed that this improvement in capsule technology may lead to increased diagnostic yields; however, real world clinical data is currently lacking.
OBJECTIVE: To evaluate the clinically relevant findings of SB3 and SB2 capsules in a population of United States veterans.
METHODS: A retrospective analysis of 260 consecutive CE studies was performed including 130 SB3 and 130 SB2 capsule studies. Recorded variables included: age, gender, type of capsule, body mass index, exam completion, inpatient status, opioid use, diabetes, quality of preparation, gastric transit time, small bowel transit time, indication, finding, and if the exam resulted in a change in clinical management. The primary outcome measured was the detection of clinically relevant findings between SB3 and SB2 capsules.
RESULTS: Mean age of the study population was 67.1 ± 10.4 years and 94.2% of patients were male. Of these 28.1% were on opioid users. The most common indications for capsule procedure were occult GI bleeding (74.6%) and overt GI bleeding (14.6%). Rates of incomplete exam were similar between SB3 and SB2 groups (16.9% vs 9.2%, P = 0.066). The overall rate of clinically relevant finding was 48.9% in our study. No significant difference was observed in SB3 vs SB2 capsules for clinically relevant findings (46.2% vs 51.5%, P = 0.385) or change in clinical management (40.8% vs 50.0%, P = 0.135).
CONCLUSIONS: Our study found no significant difference in clinically relevant findings between SB3 and SB2 capsules.