ABSTRACT BACKGROUND Microsatellite instability-high/mismatch repair-deficient (MSI-H/dMMR) tumours have a high response rate to immunotherapy. Antitumour activity and safety of serplulimab,

a novel humanised anti-PD-1 monoclonal antibody, were evaluated in this phase II study. METHODS In this ongoing, single-arm, open-label, phase II trial, patients with previously treated

unresectable or metastatic MSI-H/dMMR solid tumours received intravenous serplulimab 3 mg/kg every 2 weeks for up to 52 cycles. The primary endpoint was objective response rate (ORR)

assessed by an independent radiological review committee per Response Evaluation Criteria in Solid Tumors v1.1. Secondary endpoints included additional efficacy measures, safety, and

in 53 (49.1%) patients; immune-related adverse events occurred in 52 (48.1%) patients. CONCLUSIONS Serplulimab demonstrates a durable antitumour effect and a manageable safety profile in

previously treated patients with MSI-H solid tumours. Serplulimab is a promising tissue-agnostic treatment for previously treated MSI-H solid tumours. TRIAL REGISTRATION NCT03941574. SIMILAR

CONTENT BEING VIEWED BY OTHERS A PHASE 1/2 TRIAL OF IBRUTINIB IN COMBINATION WITH PEMBROLIZUMAB IN PATIENTS WITH MISMATCH REPAIR PROFICIENT METASTATIC COLORECTAL CANCER Article 07 April

2021 PEMBROLIZUMAB IN MICROSATELLITE-INSTABILITY-HIGH AND MISMATCH-REPAIR-DEFICIENT ADVANCED SOLID TUMORS: UPDATED RESULTS OF THE KEYNOTE-158 TRIAL Article 20 February 2025 BOTENSILIMAB PLUS

BALSTILIMAB IN RELAPSED/REFRACTORY MICROSATELLITE STABLE METASTATIC COLORECTAL CANCER: A PHASE 1 TRIAL Article Open access 13 June 2024 BACKGROUND Patients with metastatic microsatellite

instability-high (MSI-H) or mismatch repair-deficient (dMMR) tumours represent a distinct patient population. Depending on the type and stage of cancer, MSI-H/dMMR patients may have a better

(e.g. MSI-H stage I/II colorectal cancer [CRC], gastric cancer, or bladder cancer) or worse prognosis (e.g. MSI-H stage III CRC or breast cancer) and might respond poorly to chemotherapy

compared to patients with microsatellite stable/microsatellite instability-low (MSS/MSI-L) tumours [1,2,3,4,5]. MSI-H accounts for <5–33% of tumours, and a meta-analysis showed that the

frequencies were similar between Chinese and Western populations [6]. The burden of MSI-H cancers is estimated to be more than 1 million and about 0.3 million new cases per year worldwide

and in China, respectively [6,7,8,9,10]. MSI-H/dMMR tumours express a large array of neoantigens due to a high level of mutations [11, 12], and their microenvironment is characterised by

immune cell infiltration, coupled with an upregulation of immune checkpoint proteins in tumour cells [13]. These establish the biological rationale of immune checkpoint blockade for

MSI-H/dMMR tumours. The durable and encouraging tumour response observed with pembrolizumab (objective response rate [ORR] of 39.6%) across MSI-H/dMMR tumours provides evidence for the

clinical benefits of using immunotherapy [14]. Pembrolizumab received tissue-agnostic approvals for MSI-H/dMMR tumours, which marked an advancement in precision medicine [15, 16]. Nivolumab

also received an approval based on MSI-H/dMMR, but only in previously treated CRC [17]. Currently, patients with MSI-H/dMMR tumours have limited treatment options, and thus alternative

therapeutic agents may be beneficial. Serplulimab (HLX10) is a novel humanised monoclonal anti-PD-1 antibody. In a phase I study involving patients with previously treated advanced or

metastatic solid tumours (NCT03468751), serplulimab up to 10 mg/kg was safe and well tolerated [18]. Here we present data from a phase II study evaluating the antitumour activity and safety

of serplulimab 3 mg/kg in Chinese patients with unresectable or metastatic MSI-H/dMMR solid tumours in the subsequent line setting. METHODS STUDY DESIGN This ongoing, single-arm, open-label,

phase II trial was conducted at 39 study sites in China (of which 33 enrolled patients). Patients received intravenous serplulimab 3 mg/kg every 2 weeks for up to 52 cycles or until loss of

clinical benefit, unacceptable toxicity, death, or withdrawal of consent. Patients could continue serplulimab treatment after a first documented disease progression (PD) per Response

Evaluation Criteria in Solid Tumors (RECIST) v1.1 [19] if it was neither symptomatic nor rapidly progressive requiring urgent intervention, and if their Eastern Cooperative Oncology Group

performance status did not deteriorate. Subsequent treatment for patients with confirmed PD at the next assessment (≥4 weeks from the first documented PD) by response criteria for cancer

immunotherapy trials (iRECIST) [20] was at the discretion of the investigator. The trial was registered with ClinicalTrials.gov (NCT03941574). PATIENTS Eligible patients were 18–75 years of

age, had histologically or cytologically confirmed unresectable or metastatic MSI-H/dMMR solid tumours as assessed at central laboratory or study sites, and had progressed on or were

intolerant to at least one prior line of standard therapy. Previous systemic antitumour therapy must have been discontinued ≥2 weeks prior to study treatment, and adverse events (AEs) must

have resolved to at least grade 1 (graded per National Cancer Institute Common Terminology Criteria for Adverse Events v5.0, with the exception of grade 2 alopecia). Patients must have at

least one measurable lesion as per RECIST v1.1, an Eastern Cooperative Oncology Group performance status score of 0 or 1 within 7 days before initiating study treatment, adequate organ

function, and life expectancy of ≥12 weeks. Details of the inclusion and exclusion criteria are provided in Supplementary Material. ASSESSMENTS AND OUTCOMES MSI status, tumour mutational

burden (TMB), and programmed death-ligand 1 (PD-L1) expression were determined at the designated central laboratory; MSI status could also be analysed at study sites. Assessment of mismatch

repair (MMR) was performed at study sites. Tumour assessments were performed at baseline, every 6 weeks until week 48, and every 12 weeks thereafter. The primary endpoint was ORR assessed by

independent radiological review committee (IRRC) per RECIST v1.1; confirmation of complete response and partial response was required after 28 days. Secondary efficacy endpoints included

ORR assessed by IRRC (per iRECIST) and by investigators (per RECIST v1.1 and iRECIST), disease control rate (DCR; stable disease [SD] was determined ≥42 days from first study treatment),

overall survival (OS), 6- and 12-month OS rate, progression-free survival (PFS), 6- and 12-month PFS rate, and duration of response (DOR). DCR, PFS, and DOR were assessed both by IRRC and by

investigators per RECIST v1.1 and iRECIST. Other secondary endpoints included safety, pharmacokinetics (PK), immunogenicity, and health-related quality of life (HRQoL). Safety was monitored

throughout the trial and for 90 days after treatment discontinuation. AEs were coded according to Medical Dictionary for Regulatory Activities (MedDRA) v23.1 and graded per National Cancer

Institute Common Terminology Criteria for Adverse Events v5.0. Adverse events of special interest included infusion-related reactions and immune-related adverse events (irAEs) [21].

Serplulimab serum concentrations were determined for PK assessment. Immunogenicity was assessed by antidrug antibodies (ADAs) and neutralising antibodies (NAbs) against serplulimab, and

patients were considered ADA or NAb positive if they had at least one positive ADA or NAb result. HRQoL was evaluated by quality of life questionnaires. Additional assessment methods are

provided in Supplementary Material. STATISTICAL ANALYSIS Assuming an ORR of 30%, a sample size of 40 patients were required to demonstrate that the lower limit of the 95% confidence interval

(95% CI) for ORR was no lower than 15% at a one-sided 2.5% _α_-level. To account for censoring, dropout, and false positivity in detecting MSI-H/dMMR, the plan was to enrol around 100

patients. Primary and secondary efficacy endpoints were analysed primarily in the main efficacy analysis population (MEAP). Subgroup analyses were conducted to investigate the impacts of

PD-L1 expression (positive or negative), TMB status (low or high), MSI status (MSS/MSI-L or MSI-H), and tumour types (CRC or non-CRC) on efficacy. The efficacy endpoints were also analysed

in the special-interest efficacy analysis population (SIEAP) and the sensitivity analysis population (SAP), two subsets of MEAP. Point estimates and Clopper–Pearson 95% CIs were calculated

for ORR and DCR. OS, PFS, and DOR were estimated using the Kaplan–Meier method. The threshold for statistical success was a lower limit of the 95% CI of the primary endpoint being ≥15% in

both the MEAP and the SIEAP. Safety was assessed in the safety set (SS) and in the MEAP. PK was analysed in the pharmacokinetic set. Immunogenicity assessment was based on the SS. Safety,

HRQoL, PK, and immunogenicity data were summarised by descriptive statistics. Detailed definitions of the analysis sets are provided in Supplementary Material. Statistical analysis was

conducted using the SAS software, v9.4 or above (SAS Institute, NC, USA). REPORTING SUMMARY Further information on research design is available in the Nature Research Reporting Summary

linked to this article. RESULTS PATIENT CHARACTERISTICS AND DISPOSITION Between 22 July 2019 and 9 January 2021, 208 patients were screened, and 108 patients were enrolled (Fig. 1). The main

reason for exclusion was not meeting the eligibility criteria. A total of 108 patients received at least one dose of serplulimab and comprised the SS. Of these patients, 68 had MSI-H

tumours and were included in the MEAP; 58 and 42 were included in the SAP and the SIEAP, respectively. In the MEAP, CRC was the most common tumour type (53 [77.9%]). A total of 30 (44.1%)

patients were PD-L1 positive, and 55 (80.9%) were TMB-high, with a median TMB of 33.0 (Table 1). Baseline characteristics of patients in the SIEAP and SS were largely similar to those in the

MEAP, except for a higher proportion of patients with TMB-H tumours in the MEAP (80.9%) and SIEAP (71.4%) than the SS (52.8%). As of data cutoff (9 January 2021), the median duration of

follow-up in the MEAP was 7.7 months (range, 1.1–16.4). The median duration of treatment exposure was 210 days; 11 patients completed the study, and 31 discontinued treatment due to PD (19

[27.9%]), poor compliance (4 [5.9%]), death (3 [4.4%]), AE (2 [2.9%]), delayed dose (2 [2.9%]), and other reason (1 [1.5%]). The numbers of patients who completed the study and those who

discontinued treatment were 36 and 69 in the SS and 7 and 23 in the SIEAP, respectively. EFFICACY In the MEAP, a confirmed objective response by IRRC per RECIST v1.1 was observed in 26

patients (ORR, 38.2%; 95% CI, 26.7–50.8), including 2 (2.9%) patients with complete response and 24 (35.3%) with partial response (Table 2), with the lower limit of 95% CI of ORR meeting the

prespecified threshold of positive results (≥15%). In addition, 20 (29.4%) patients had SD by IRRC per RECIST v1.1, contributing to a DCR of 67.6% (95% CI, 55.2–78.5). The best percentage

change from baseline in target lesion size in the MEAP is presented in Fig. 2. The median DOR was not reached, with 95.7% (95% CI, 72.9–99.4) of patients estimated to have a DOR of ≥6 and

≥12 months. Similarly, in the SIEAP, IRRC-assessed ORR per RECIST v1.1 was 31.0% (95% CI, 17.6–47.1), which also met the threshold for statistical success (Table 2). IRRC-assessed DCR per

RECIST v1.1 was 54.8% (95% CI, 38.7–70.2). Median DOR was not reached in this population, with 90.9% (95% CI, 50.8–98.7) of patients estimated to have a DOR of ≥6 and ≥12 months. Twenty-six

(38.2%) patients in the MEAP had PFS events (23 had PD as assessed by IRRC per RECIST v1.1, and 3 died without PD). Median PFS was not reached (Fig. 3). The estimated 6- and 12-month PFS

rates were both 61.9% (95% CI, 49.0–72.5). In the SIEAP, median PFS (by IRRC per RECIST v1.1) was 4.2 months (95% CI, 2.2–not reached [NR]), with estimated 6- and 12-month PFS rates being

49.7% (95% CI, 33.4–64.1). A consistently favourable antitumour activity for serplulimab was demonstrated by IRRC assessments per iRECIST and by investigator assessments per RECIST v1.1 or

iRECIST (Supplementary Tables S1 and S2). Twelve patients in the MEAP had died by data cutoff (Fig. 3). Median OS was not reached (95% CI, 16.0–NR). The estimated 6- and 12-month OS rates

were 88.2% (95% CI, 77.7–93.9) and 81.2% (95% CI, 67.8–89.4), respectively. OS was similar in the SIEAP (median OS [95% CI], NR [NR–NR]; 6-month OS rate, 90.5% [76.6–96.3]; 12-month OS rate,

78.4% [58.3–89.6]). Efficacy results were consistent in the SAP (Supplementary Table S3). Subgroup analysis was based on tumour assessments by IRRC per RECIST v1.1 and OS. Among all

enrolled patients, MSI-H patients achieved a greater ORR (38.2% vs 2.8%), a greater DCR (67.6% vs 19.4%), a longer PFS (median PFS [95% CI], NR [4.2–NR] vs 1.4 months [1.3–1.6]), and a

longer OS (median OS, NR [16.0–NR] vs 5.0 months [4.0–9.4]) compared with MSS/MSI-L patients. In the MEAP, ORR was numerically higher in PD-L1-positive patients (Supplementary Table S4).

Median PFS and median OS were longer in TMB-high patients, while the differences in ORR and DCR were not pronounced. ORR was similar between patients with CRC and those with non-CRC tumours,

although there was a trend of longer DOR in CRC patients. Among patients in the MEAP who had discontinued or completed serplulimab treatment, 8 (11.8%) patients received antitumour

chemotherapy, 3 (4.4%) received subsequent radiation therapy, 2 (2.9%) received surgery, and 15 (22.1%) were treated with other antitumour therapies. QUALITY OF LIFE Most patients

experienced improved or stable HRQoL relative to baseline as assessed by quality of life questionnaires (Supplementary Tables S5 and S6). SAFETY Among patients in the SS, 105 (97.2%)

patients reported at least one treatment-emergent adverse event (TEAE) (Table 3). The most common TEAEs were anaemia (34.3%), hypoproteinaemia (27.8%), and increased aspartate

aminotransferase (25.0%). Grade ≥3 TEAEs occurred in 53 (49.1%) patients, the most common being anaemia (8.3%), PD (6.5%), increased gamma-glutamyltransferase (5.6%), and intestinal

obstruction (5.6%). Adverse drug reactions (ADRs) occurred in 86 (79.6%) patients (Table 3 and Supplementary Table S7), and most events were grade 1 or 2. Serious ADRs occurred in 16 (14.8%)

patients. Three (2.8%) patients discontinued serplulimab treatment because of ADRs, including abnormal liver function (2 [1.9%]), immune-mediated liver injury (1 [0.9%]), pneumonitis (1

[0.9%]), and fever (1 [0.9%]). Three (2.8%) patients had grade 5 ADRs as assessed by investigators: one had intestinal obstruction and one experienced PD after receiving serplulimab, and 

both events were considered as possibly related to the study drug; one patient experienced PD after withdrawal, with the exact cause of death unknown. Adverse events of special interest

occurred in 52 (48.1%) patients and all were irAEs, the most common being hypothyroidism (18 [16.7%]) and hyperthyroidism (9 [8.3%]; Table 3). Most irAEs were grade 1 or 2 in severity, and

grade ≥3 irAEs occurred in 10 (9.3%) patients; there were no grade 5 irAEs. No infusion-related reactions occurred in this study. The incidences and severity of TEAEs in the MEAP were

largely consistent with those in the SS (Table 3). PHARMACOKINETICS The mean trough concentration of serplulimab increased as treatment cycle increased, indicating an accumulation of

serplulimab (Supplementary Fig. S1). There was a trend toward lower accumulation in terms of trough concentration in ADA-positive, PD-L1-negative, TMB-low, and MSS/MSI-L subgroups

(Supplementary Table S8). IMMUNOGENICITY ADAs were detected in 5/108 patients (4.6%). No patients had detectable NAbs. DISCUSSION Serplulimab treatment resulted in durable and clinically

meaningful tumour responses in Chinese patients with previously treated unresectable or metastatic MSI-H solid tumours. This study met the prespecified primary endpoint. ORR (38.2% as

assessed by IRRC per RECIST v1.1) was comparable with that observed with pembrolizumab in MSI-H/dMMR solid tumours (39.6% based on a pooled analysis of five trials [14]) and with that for

nivolumab in MSI-H/dMMR CRC (31.1%) [22]. Most of the patients still had ongoing tumour response at the data cutoff, with an estimated 95.7% of patients having a DOR of ≥1 year. The safety

profile of serplulimab was consistent with that for PD-1 inhibitors. Serplulimab demonstrated a sustained effect on MSI-H solid tumours, and this benefit was observed irrespective of

previous lines of therapy. Patients with CRC and those with non-CRC tumours seemed to have similar responses to serplulimab treatment based on the ORR, though further studies with large

sample sizes are needed to confirm the result. Moreover, the durable response was coupled with maintenance or improvements of HRQoL in most patients. The mature data on PFS and OS from this

ongoing trial will provide further insight into the clinical efficacy. Tumour responses assessed by RECIST v1.1 and iRECIST in this study provided additional evidence for the antitumour

activity of serplulimab. In this study, outcomes were mostly consistent when evaluated by RECIST and by iRECIST. However, median PFS was shorter in the SIEAP when assessed per RECIST v1.1

than according to iRECIST (4.2 vs NR by IRRC or by the investigators), which may be due to misclassification of pseudoprogression as PD by RECIST v1.1. Nevertheless, similar outcomes

according to assessment by IRRC and by the investigators add to the robustness of the tumour response results. Discordance between MMR protein testing and MSI DNA testing results have been

reported by previous studies, ranging from 1 to 10% [23, 24]. In our study, MSI-H and dMMR overlapped partially, as 68 patients were MSI-H out of 108 patients identified as MSI-H or dMMR.

The discordance may be due to differences in the sensitivity and specificity of techniques used, misinterpretation of testing results, or possibly biological reasons, such as functional

redundancy of proteins for DNA mismatch repair and MSI-H originating from other genetic defects [24,25,26,27]. Caution should be taken when using MMR immunohistochemistry testing as a

screening tool given occasional equivocal staining patterns, sometimes inadequate sensitivity due to antibodies used, requirements of pathologist’s experience, and other pitfalls

[23,24,25,26]. To circumvent these pitfalls, we used MSI DNA testing to select target patient population for serplulimab; MSI-H as a predictor of tumour response to serplulimab was supported

by a better response in MSI-H patients than MSS/MSI-L patients. Understanding the response to immune checkpoint inhibitors in MSI-H tumours is of interest, with high TMB shown to be

predictive of better clinical outcomes in MSI-H cancers treated with immune checkpoint inhibitors [28, 29]. In contrast, tumour response to PD-1 inhibitors was found to be consistent across

PD-L1 positive and negative MSI-H/dMMR tumours in the KEYNOTE-016 and CheckMate 142 studies [22, 30]. Although numerical differences were observed in terms of ORR or PFS in our subgroup

analyses according to PD-L1 expression and TMB, results were inconclusive given the small differences between groups and the small sample size, especially in the TMB-low group. The TEAEs

reported in this study were in line with AE profiles for other immunotherapies [14, 31]. The most frequent grade ≥3 events and irAEs are also commonly observed during treatment with

pembrolizumab in solid tumour patients [32, 33]. For the three patients with grade 5 ADRs as determined by investigators, the sponsor assessment suggested that these cases were possibly

unrelated to serplulimab, but probably due to PD as well as peritoneal metastasis and adhesion (for the case with intestinal obstruction), and underlying diseases (for two cases with PD).

Limitations of this study included lack of a comparator, a small sample size, and overrepresentation of CRC patients. Moreover, the interpretation of subgroup analysis by TMB was limited by

the small number of patients who were TMB-low. As _RAS_ mutation was shown to be associated with a shorter PFS in MSI-H/dMMR CRC patients treated with pembrolizumab in first-line setting

[34], subgroup analysis according to _BRAF_, _KRAS_, and _NRAS_ mutation status is recommended in future studies. In conclusion, serplulimab provided encouraging efficacy and manageable

safety profile in Chinese patients with unresectable or metastatic MSI-H solid tumours who have progressed on or been intolerant to at least one prior line of standard therapy, regardless of

tumour type. Based on these results, the China National Medical Products Administration has granted priority review designation to serplulimab for treating this patient population. DATA

AVAILABILITY The data generated in this study are available from the corresponding author upon reasonable request. CHANGE HISTORY * _ 02 NOVEMBER 2022 A Correction to this paper has been

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microsatellite-instability-high advanced colorectal cancer. N. Engl J Med. 2020;383:2207–18. Article  CAS  PubMed  Google Scholar  Download references ACKNOWLEDGEMENTS We would like to

express our gratitude to the patients who participated in the trial, their families, the principal investigators, clinicians, study coordinators, and nurses. We thank the clinical study team

(Clinical Operations: Weiwei Zhang, Guiyu Yang, Jing Li; Statistics: Wenting Qiu, Jiancheng Cheng; Pharmacokinetics: Xiaodi Zhang, Liang Zhou) and Wenjie Zhang from Shanghai Henlius

Biotech, Inc. for their support in study execution, study design, data acquisition, statistical analyses, and manuscript revisions. Medical writing support was provided by Xinlei Yu and

Chris Langford of Parexel and Shiqi Zhong and Chen Hu from Shanghai Henlius Biotech, Inc. and funded by Shanghai Henlius Biotech, Inc. FUNDING This work was supported by Shanghai Henlius

Biotech, Inc. AUTHOR INFORMATION Author notes * These authors contributed equally: Shukui Qin, Jin Li. * A full list of members and their affiliations appears in the Supplementary

Information. AUTHORS AND AFFILIATIONS * Department of Oncology, Qinhuai Medical Area, Eastern Theater General Hospital of PLA China, Nanjing, China Shukui Qin * Department of Oncology,

Tongji University Shanghai East Hospital, Shanghai, China Jin Li * Department of Abdominal Oncology, Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer

Hospital), Hangzhou, China Haijun Zhong * Department of Oncology, Affiliated Cancer Hospital and Institute of Guangzhou Medical University, Guangzhou, China Chuan Jin * Department of

Hematology and Oncology, Taizhou First People’s Hospital, Taizhou, China Lili Chen * Department of Oncology, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China

Xianglin Yuan * Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China Qingxia Fan * Department of Oncology, The People’s Hospital of Guangxi Zhuang

Autonomous Region, Nanning, China Kehe Chen * Department of Oncology, The Third Xiangya Hospital of Central South University, Changsha, China Peiguo Cao * Chemotherapeutic Department,

Zhongshan City People’s Hospital, Zhongshan, China Jianjun Xiao * Department of Oncology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China Da Jiang * Department of

Oncology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China Tao Zhang * Cancer Center, The Fifth Affiliated Hospital Sun Yat-sen University, Zhuhai, China

Hongyu Zhang * Department of Oncology, The First Affiliated Hospital of Guangdong Pharmaceutical University, Guangzhou, China Xicheng Wang * Department of Gastrointestinal Oncology, The

First People’s Hospital of Foshan, Foshan, China Wei Wang * Shanghai Henlius Biotech, Inc., Shanghai, China Lin Han, Qingyu Wang & Jun Zhu Authors * Shukui Qin View author publications

You can also search for this author inPubMed Google Scholar * Jin Li View author publications You can also search for this author inPubMed Google Scholar * Haijun Zhong View author

publications You can also search for this author inPubMed Google Scholar * Chuan Jin View author publications You can also search for this author inPubMed Google Scholar * Lili Chen View

author publications You can also search for this author inPubMed Google Scholar * Xianglin Yuan View author publications You can also search for this author inPubMed Google Scholar * Qingxia

Fan View author publications You can also search for this author inPubMed Google Scholar * Kehe Chen View author publications You can also search for this author inPubMed Google Scholar *

Peiguo Cao View author publications You can also search for this author inPubMed Google Scholar * Jianjun Xiao View author publications You can also search for this author inPubMed Google

Scholar * Da Jiang View author publications You can also search for this author inPubMed Google Scholar * Tao Zhang View author publications You can also search for this author inPubMed 

Google Scholar * Hongyu Zhang View author publications You can also search for this author inPubMed Google Scholar * Xicheng Wang View author publications You can also search for this author

inPubMed Google Scholar * Wei Wang View author publications You can also search for this author inPubMed Google Scholar * Lin Han View author publications You can also search for this

author inPubMed Google Scholar * Qingyu Wang View author publications You can also search for this author inPubMed Google Scholar * Jun Zhu View author publications You can also search for

this author inPubMed Google Scholar CONSORTIA THE SERPLULIMAB-MSI-H INVESTIGATORS * Shukui Qin * , Jin Li * , Haijun Zhong * , Chuan Jin * , Lili Chen * , Xianglin Yuan * , Qingxia Fan * , 

Kehe Chen * , Peiguo Cao * , Jianjun Xiao * , Da Jiang * , Tao Zhang * , Hongyu Zhang * , Xicheng Wang *  & Wei Wang CONTRIBUTIONS SQ and JL contributed to study conception and design.

SQ, JL, HZ, CJ, LC, XY, QF, KC, PC, JX, DJ, TZ, HZ, XW, WW, LH, QW, and JZ contributed to data collection, analysis, and interpretation; they all reviewed and approved the final submitted

manuscript. All other Serplulimab-MSI-H Investigators contributed to data collection and analysis. CORRESPONDING AUTHOR Correspondence to Jin Li. ETHICS DECLARATIONS COMPETING INTERESTS LH,

QW, and JZ are employees of Shanghai Henlius Biotech, Inc. All other authors declare no competing interests. ETHICS APPROVAL AND CONSENT TO PARTICIPATE The study protocol, any amendments,

and informed consent were approved by central or independent institutional review board/ethics committee at participating sites. The study was conducted in accordance with the principles of

the Declaration of Helsinki, Good Clinical Practice guidelines, and local applicable regulatory requirements. All participants provided written informed consent. CONTENT FOR PUBLICATION Not

applicable. ADDITIONAL INFORMATION PUBLISHER’S NOTE Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. The original online

version of this article was revised: The original version of this article contained a mistake in the PDF as the corresponding author Jin Li is missing from the Consortia information. We

apologize for the error. The original article has been corrected. SUPPLEMENTARY INFORMATION SUPPLEMENTARY MATERIAL REPORTING GUIDELINES-CONSORT CHECKLIST REPORTING SUMMARY (REPRODUCIBILITY

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ARTICLE Qin, S., Li, J., Zhong, H. _et al._ Serplulimab, a novel anti-PD-1 antibody, in patients with microsatellite instability-high solid tumours: an open-label, single-arm, multicentre,

phase II trial. _Br J Cancer_ 127, 2241–2248 (2022). https://doi.org/10.1038/s41416-022-02001-3 Download citation * Received: 29 January 2022 * Revised: 07 September 2022 * Accepted: 23

September 2022 * Published: 19 October 2022 * Issue Date: 07 December 2022 * DOI: https://doi.org/10.1038/s41416-022-02001-3 SHARE THIS ARTICLE Anyone you share the following link with will

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