Concomitant administration of lenvatinib and camrelizumab for the treatment of hepatocellular carcinoma, and its effect on hepatocellular carcinoma control

Purpose: To study the efficacy of combined use of lenvatinib and camrelizumab in hepatocellular carcinoma (HCC) therapy, and its impact on disease control rate (DCR). Methods: The medical records of 92 HCC patients treated at the Oncology Department of The People’s Hospital of Dongying, Dongying, China (April 2019-April 2020), were chosen for analysis, and assigned into study group (SG, n = 46) and reference group (RG, n = 46) based on odd and even hospital admission no. All patients received specific routine treatments. In addition, SG was treated with lenvatinib in combination with camrelizumab. After treatment, liver function and levels of serum tumor markers were determined. Results: Compared with RG, SG had significantly lower levels of liver function indices {alanine aminotransferase (ALT), total bilirubin (TBiL), and aspartate aminotransferase (AST)} and lower levels of serum tumor markers {alpha-fetoprotein (AFP), alpha-fetoprotein variant (AFP-L3) and Golgi protein 73 (GP73)} (p < 0.001); higher DCR (p < 0.05), lower score in Eastern Cooperative Oncology Group (ECOG), and higher Karnofsky (KPS) score (p < 0.001). Conclusion: The combined use of lenvatinib and camrelizumab may be a reliable strategy for reducing serum tumor marker levels in HCC patients, improving liver function and patients’ performance status, and enhancing DCR.


INTRODUCTION
Hepatocellular carcinoma (HCC), a malignant tumor which occurs within the intrahepatic cholangiocytes or hepatocytes, seriously threatens human health, and it results in high morbidity and mortality [1]. With the current rise in incidence of HCC, nearly half of HCC occurs in Chinese people, mostly as a result of viral infection. Since HCC has an insidious onset, majority of the patients have no abnormal physical manifestations in the early stage, such that most times, it is only at the middle and late stages of the disease that they feel great discomfort [2].
Investigations have revealed that about 80 % of HCC patients are medically unfit for radical resection at the time of diagnosis. At present, the use of molecular level-targeted drugs is one of the reliable methods for treating middle and advanced HCC [3]. Lenvatinib is a multi-targeted tyrosine kinase inhibitor (TKI) which not only inhibits tumor proliferation but also selectively suppresses the kinase activity of vascular endothelial growth factor (VEGF) receptors [4]. This drug obtained the approval of the U.S. Food and Drug Administration (USFDA) for first-line use in the treatment of liver cancer in 2018 [5].
A recent clinical study showed that camrelizumab, an independently-developed PD-1 inhibitor in China with sustained antitumor effects, has achieved remarkable results in treating diseases such as refractory NSCLC and primary liver cancer with lung metastasis [6]. However, not much is known about the treatment of HCC in China using a combination of lenvatinib and camrelizumab. This study was aimed at investigating the clinical effect of combined use of lenvatinib and camrelizumab in treating HCC, and its effect on disease control rate (DCR).

Patients' profiles
The medical records of 92 HCC patients treated in the Oncology Department of The People's Hospital of Dongying, Dongying, China (April 2019 -April 2020) were chosen for retrospective analysis, and they were assigned to study group (SG, n = 46) and reference group (RG, n = 46), based on odd and even hospital admission no.

Ethical approval
Approved by the ethics committee of The People's Hospital of Dongying, Dongying (approval no. 20190144), this study followed the guidelines of the 2013 World Medical Association Declaration of Helsinki [7].

Inclusion criteria
The enrolled subjects were those meeting the diagnostic criteria for HCC in the Specification for Diagnosis and Treatment of Hepatocellular Carcinoma (2019 version) [8]: patients who had basic well-enough conditions and could accept targeted therapy, those who were not given any other cancer treatments and who had the entire treatment in The People's Hospital of Dongying, patients with normal functions in vital organs such as heart, and those with normal bone marrow hematopoiesis.

Exclusion criteria
The excluded patients were those with severe hemorrhagic tendency or abnormal hemogram, patients suffering from refractory massive ascites, dyscrasia or active infection, those who could not cooperate with treatment or follow-up due to disturbance of consciousness, and those with bleeding from esophageal varices 1 month before treatment.

Treatments
All patients received specific routine treatments such as liver protection therapy with glycyrrhizin injection (CSPC Ouyi Pharmaceutical Co. Ltd.; NMPA approval no. H20065475; specification: 20 mL), and symptomatic and supportive treatment with ceftriaxone sodium injection (Shanghai Roche Pharmaceuticals Ltd.; NMPA approval no. H10983036; specification: 1 g×1 bottle/box), and compound amino acid injection (Sichuan Kelun Pharmaceutical Co. Ltd.; NMPA approval no. H19993590; specification: 500 mL: 25 g/bottle). In addition, patients in SG received lenvatinib in combination with camrelizumab. Lenvatinib (Beacon Pharmaceuticals Limited; NMPA approval no. H20180052; specification: 4 mg x 10 pills x 3 plates) was orally administrated at a dose of 12 mg/day for patients with body mass ≥ 60 kg, and at a dose of 8 mg/day for patients with body mass < 60 kg. In addition, 3 mg/kg camrelizumab (Suzhou Shengdiya Biomedicine Co. Ltd.; NMPA approval no. S20190027; specification: 200 mg/bottle) was administered once every two weeks via intravenous drip. The treatment dose and interval of administration were adjusted properly based on patients' adverse drug reactions. Each patient's blood pressure was monitored daily until the disease condition progressed or the patient asked for drug withdrawal.

Liver function and serum tumor markers
After treatment, fasting venous blood (5 mL) was drawn from each patient in each group, and was centrifuged to obtain the supernatant (serum). The serum levels of alanine aminotransferase (ALT), total bilirubin (TBiL), and aspartate aminotransferase (AST) were measured using automatic biochemical analyzer model iChem-540 (Shenzhen iCubio Biomedical Technology Co. Ltd). The levels of serum tumor markers i.e., alpha-fetoprotein (AFP), alpha-fetoprotein variant (AFP-L3) and golgi protein 73 (GP73) were  measured with chemiluminescence, microcentrifuge column method, and ELISA, respectively.

Treatment efficacy
All patients received MRI imaging examination before treatment for the determination of tumor status, and were reviewed with the same examination method after treatment. Treatment efficacy was divided into complete response (CR, i.e., complete disappearance of lesions and no new lesions after treatment), partial response [PR, ≥ 30 % decrease in the sum of the longest diameters of target lesions (SUM)], stable disease (SD, < 30 decrease in the SUM, or < 20 increase in the SUM), and progressive disease (PD, ≥ 20 % increase in the sum of the longest diameters of target lesions, or new lesions). Disease control rate (DCR) was calculated as shown in Eq 1: where DCR = Disease control rate; CR = number of patients with complete response; PR = number of patients with partial response; SD = number of patients with stable disease; T = total number of patients.

Performance status
Each patient's performance status after treatment was assessed using the Eastern Cooperative Oncology Group (ECOG) [9]. The specific scoring criteria are shown in Table 1.

Physical condition
The patients' physical condition after treatment was assessed with Karnofsky (KPS) score (0-100 points), with a higher score demonstrating better physical condition [10].

Statistical analysis
In this study, data were processed using the professional statistical software SPSS24.0. Graphs were prepared with GraphPad Prism 7 (GraphPad Software, San Diego, USA). Enumeration data are expressed as numbers and percentages [n (%)], and were tested with χ 2 test, while measurement data are presented as mean ± SD, and were tested with t-test. Differences were considered statistically significant at p < 0.05. Table 2 presented no statistical differences between the two groups with respect to general patient data such as mean age, Child-Pugh grade, blood platelet count, and degree of education (p > 0.05).

Liver function
After treatment, there were markedly lower levels of various liver function indicators in SG than in RG (p < 0.001; Table 3). Table 4 showed a higher DCR in SG than in RG (p < 0.05).

Levels of serum tumor markers
After treatment, the levels of various serum tumor markers were lower in SG than in RG (p < 0.001; Table 5). Capable of only limited self-care, confined to bed or chair more than 50 % of waking hours. 4 Cannot carry on any self-care. Totally confined to bed or chair. 5 Dead    2 5.392 P-value < 0.05 Note: CR = complete response; PR = partial response; SD = stable disease; PD = progressive disease; DCR = disease control rate

DISCUSSION
Hepatocellular carcinoma (HCC) is a malignant neoplastic disease with high morbidity and mortality worldwide [11]. The disease, which is related to hepatic viral infections (HCV and HBV), occurs mainly in Asia, with nearly half of the cases in China. Therefore, diagnosis and treatment of HCC constitute a major challenge for healthcare workers [12]. There are limited treatments and a poor prognosis for HCC patients, with a median survival of about 1 year.
Surveys have found that about 50 % of patients are in the late stage at diagnosis and are unable to undergo surgical treatment, thereby making systemic therapy the primary modality [13]. Since sorafenib was approved for HCC treatment in November 2007, no breakthrough or progress has been observed in related therapeutic agents until an international multi-center and randomized controlled study in 2018 introduced the new option, lenvatinib [14].
An oral multi-target inhibitor for the treatment of cancer, lenvatinib not only counteracts tumor angiogenesis and promotes vascular normalization [15], it also improves immune function. Clinically, it is effective in treating locally recurrent or metastatic and progressive, radioiodine, intractable differentiated thyroid cancer, as well as treating renal cancer patients who have received VEGF-targeted therapy [16].
Currently, camrelizumab is approved for treating relapsed or refractory lymphoma. In a study in which camrelizumab was clinically applied in the treatment of advanced HCC patients, the results showed a DCR (44.2 %) [17]. Although the overall incidence of adverse effects was high, the reactions due to camrelizumab were mild, with only 13.2 % of severe adverse events of grade 3 and above. These results suggest that camrelizumab has promising antineoplastic activity and controllable toxicity, and may serve as a novel treatment option for HCC patients [18].
Based on a previous clinical treatment experience, this study applied lenvatinib in combination with camrelizumab to HCC patients, showing a higher DCR in SG than in RG (93.48 % vs 76.09 %). Thus, the combined therapy effectively enhanced the DCR for HCC patients and exerted positive effects on the prognosis of patients. Serum tumor markers are important indices for diagnosing diseases and assessing prognosis in the clinic [19]. For example, AFP-L3, a marker unique to HCC cells, accurately reflects the degrees of intravascular invasion and metastasis in patients, and its levels are positively correlated with the degree of tumor deterioration.
In addition, GP73, a transmembrane protein on the Golgi body, is lowly expressed in biliary epithelial cells and hepatic cells of healthy people, but it is highly expressed in disease conditions [20]. The present study demonstrated lower post-treatment levels of AFP-L3 and GP73 in SG than in RG. This confirms that the combined treatment lowered the serum levels of tumor markers in HCC patients.

Limitations of the study
Due to short follow-up time and small sample size, this retrospective study lacks the confirmation derivable from clinical controlled trials. Moreover, some hidden adverse reactions in patients were not monitored. These deficiencies may lead to some bias in the results obtained in this study. Therefore, more studies with longer follow-up times and larger sample sizes are needed to verify the findings in this study.

CONCLUSION
The combination of lenvatinib and camrelizumab produces significant clinical efficacy in the treatment of HCC patients through improvement of physical health status, reduction in serum levels of tumor markers, enhancement of patients' recovery, and improvement of prognosis.

Acknowledgements
None provided.

Funding
None provided.

Ethical approval
None provided.

Availability of data and materials
The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Conflict of Interest
No conflict of interest associated with this work.

Contribution of Authors
We declare that this work was done by the authors named in this article, and all liabilities pertaining to claims relating to the content of this article will be borne by the authors. Ruibao Liu and Xing Wang conceived and designed the study, and drafted the manuscript. Ruibao Liu, Xiaolei Zhang, Wei Wei and Xing Wang collected, analyzed and interpreted the experimental data. Xiaolei Zhang, Xing Wang revised the manuscript for important intellectual contents. All authors read and approved the final manuscript.

Open Access
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