Eflapegrastim's enhancement of efficacy compared with pegfilgrastim in neutropenic rats supports potential for same-day dosing

Engineered polyspecific antibodies: A new frontier in the field of immunotherapeutics

The 21st-century beginning remarked with the huge success of monospecific MAbs, however, in the last couple of years, polyspecific MAbs (PsAbs) have been an interesting topic and show promise of being biobetter than monospecific MAbs. Polyspecificity, in which a single antibody serves multiple specific target binding, has been hypothesized to contribute to the development of a highly effective antibody repertoire for immune defence. This polyspecific MAb trend represents an explosion that is gripping the whole pharmaceutical industry. This review is concerned with the current development and quality enforcement of PsAbs. All provided literature on monospecific MAbs and polyspecific MAbs (PsAbs) were searched using various electronic databases such as PubMed, Google Scholar, Web of Science, Elsevier, Springer, ACS, Google Patent and books via the keywords Antibody engineering, Polyspecific antibody, Conventional antibody, non-conventional antibody, and Single domain antibody. In the literature, there are more than 100 different formats to construct PsAb by quadroma technology, chemical conjugation and genetic engineering. Till March 2023, nine PsAb have been approved around the world, and around 330 are in advanced developmental stages, showing the dominancy of PsAb in the growing health sector. Recent advancements in protein engineering techniques and the fusion of non-conventional antibodies have made it possible to create complex PsAbs that demonstrate higher stability and enhanced potency. This marks the most significant achievement for cancer immunotherapy, in which PsAbs have immense promise. It is worth mentioning that seven out of the nine PsAbs have been approved as anti-cancer therapy. As PsAbs continue to acquire prominence, they could pave the way for the development of novel immunotherapies for multiple diseases.

Efbemalenograstim alfa not inferior to pegfilgrastim in providing neutrophil support in women with breast cancer undergoing myelotoxic chemotherapy: results of a phase 2 randomized, multicenter, open-label trial

PURPOSE

Evaluate the safety and efficacy of efbemalenograstim alfa for neutrophil support in breast cancer patients undergoing myelosuppressive chemotherapy in a phase 2, dose-finding, open-label study (NCT01648322, ClinicalTrials.gov, 2012-07-19).

METHODS

232 patients received up to 4 cycles of chemotherapy, 141 patients with docetaxel + cyclophosphamide (TC) and 91 patients with docetaxel + doxorubicin + cyclophosphamide (TAC). Patients were randomized to efbemalenograstim alfa (80, 240, or 320 µg/kg [TC]; 240 or 320 µg/kg [TAC]) or pegfilgrastim (6 mg) on Day 2 of each cycle.

RESULTS

Efbemalenograstim alfa was non-inferior to pegfilgrastim in duration of moderate and severe neutropenia (absolute neutrophil count [ANC] < 1.0 × 109/L) in TAC Cycle 1 (mean [SD] of 2.1 [1.58] and 2.1 [1.46] days for 240 µg/kg and 320 µg/kg efbemalenograstim alfa, respectively, and 1.8 [1.28] days for pegfilgrastim), with a difference (95% CI) of 0.3 (-0.4, 1.1) days. ANC nadir occurred between Days 7-8 of TAC Cycle 1, with mean [SD] of 0.68 [1.064], 0.86 [1.407] and 0.78[1.283] × 109/L for 240 µg/kg, 320 µg/kg efbemalenograstim alfa and pegfilgrastim, respectively. Time to ANC recovery post nadir (defined as an ANC > 2.0 × 109/L after the expected ANC nadir) was 2.0-2.4 and 1.9 days for TAC patients treated with efbemalenograstim alfa and pegfilgrastim, respectively. No significant difference was found between any dose of efbemalenograstim alfa and pegfilgrastim in TAC Cycle 1 for incidence of moderate to severe neutropenia (76%-77% of patients) or incidence of severe neutropenia (ANC < 0.5 × 109/L; 63%-72%). Efbemalenograstim alfa exhibited similar safety profile to pegfilgrastim. Febrile neutropenia occurred in 4 (1.8%) patients, 2 patients each for 320 µg/kg efbemalenograstim alfa and pegfilgrastim, with no event considered related to study drug.

CONCLUSION

Efbemalenograstim alfa was comparable to pegfilgrastim in efficacy and safety.

CLINICALTRIALS

GOV IDENTIFIER

NCT01648322.

The impact of new and emerging agents on outcomes for febrile neutropenia: addressing clinical gaps

PURPOSE OF REVIEW

While chemotherapy treatment options for patients with solid and hematologic malignancies have dramatically improved over recent years, chemotherapy-induced neutropenia (CIN) and febrile neutropenia (FN) remain major barriers to delivering treatment at full doses and optimal timing. Despite concurrent advances in granulocyte colony-stimulating factor (G-CSF) administration, multiple barriers to the administration of and disparities in the access to these agents remain. The introduction of new, emerging agents, including biosimilars and novel therapies show promise in improving outcomes for CIN.

RECENT FINDINGS

The introduction of biosimilar filgrastim products has improved access to G-CSF administration by driving marketplace competition and has reduced costs for both patients and healthcare systems without sacrificing efficacy. Emerging therapies to address similar issues include long-acting G-CSF products, efbemalenograstim alfa and eflapegrastin-xnst, as well as agents with novel mechanisms of action, plinabulin and trilaciclib. These agents have shown efficacy and cost-saving benefits in certain populations and disease groups.

SUMMARY

Multiple emerging agents show promise in decreasing the burden of CIN. Use of these therapies will reduce access disparities and will improve outcomes for patients with cancer receiving cytotoxic chemotherapy. Many ongoing trials are underway to evaluate the roles of these agents for more widespread use.

HM15912, a Novel Long-Acting Glucagon-Like Peptide-2 Analog, Improves Intestinal Growth and Absorption Capacity in a Male Rat Model of Short Bowel Syndrome

Extensive bowel resection caused by various diseases that affect the intestines, such as Crohn's disease, volvulus, and cancer, leads to short bowel syndrome (SBS). Teduglutide is the only approved glucagon-like peptide-2 (GLP-2) drug for SBS; however, it requires daily administration. A novel GLP-2 analog with a prolonged duration of action to reduce dosing frequency and promote a greater efficacy may provide patients with a better quality of life. In the present study, the sustained exposure of HM15912 was characterized in normal male rats. The efficacy of HM15912 on intestinal growth and absorption capacity was also evaluated in normal male mice, rats, and SBS rats. HM15912 exhibited a remarkably extended half-life (42.3 hours) compared with teduglutide (0.6 hours) in rats. Despite somewhat lower in vitro potency on GLP-2 receptor than human GLP-2 or teduglutide, this longer-lasting mode of action promotes HM15912 to be more effective in terms of small intestinal growth than existing GLP-2 analogs even with a less frequent dosing interval of as little as once a week in rodents, including SBS rats. Furthermore, the small intestinal weight was approximately doubled, and the D-xylose absorption was significantly increased after pre-treatment of existing GLP-2 analogs on the market or under clinical development followed by HM15912 in rodents. These results indicate that HM15912 possesses a significant small bowel trophic effect driven by continuously increased exposure, supporting that HM15912 may be a novel treatment option with greater efficacy and the longest dosing interval among existing GLP-2 analogs for SBS with intestinal failure. SIGNIFICANCE STATEMENT: HM15912, a novel long-acting glucagon-like peptide-2 (GLP-2) analog, has a significant small bowel hypertrophic effect in rodents with a reduced frequency of administration compared to the existing GLP-2 analogs on the market or currently under clinical development. This study supports the possibility that HM15912 could be administered much less frequently than other long-acting GLP-2 analogs for patients with short bowel syndrome.

New insight into strategies used to develop long-acting G-CSF biologics for neutropenia therapy

Over the last 20 years, granulocyte colony-stimulating factors (G-CSFs) have become the major therapeutic option for the treatment of patients with neutropenia. Most of the current G-CSFs require daily injections, which are inconvenient and expensive for patients. Increased understanding of G-CSFs' structure, expression, and mechanism of clearance has been very instrumental in the development of new generations of long-acting G-CSFs with improved efficacy. Several approaches to reducing G-CSF clearance via conjugation techniques have been investigated. PEGylation, glycosylation, polysialylation, or conjugation with immunoglobulins or albumins have successfully increased G-CSFs' half-lives. Pegfilgrastim (Neulasta) has been successfully approved and marketed for the treatment of patients with neutropenia. The rapidly expanding market for G-CSFs has increased demand for G-CSF biosimilars. Therefore, the importance of this review is to highlight the principle, elimination's route, half-life, clearance, safety, benefits, and limitations of different strategies and techniques used to increase the half-life of biotherapeutic G-CSFs. Understanding these strategies will allow for a new treatment with more competitive manufacturing and lower unit costs compared with that of Neulasta.

A Randomized, Double-Blind, Placebo- and Active-Controlled, Escalating Single-Dose Study to Evaluate the Safety, Tolerability, Pharmacokinetic, and Pharmacodynamic Profiles of Subcutaneous Eflapegrastim in Healthy Japanese and Caucasian Subjects

Background

Eflapegrastim (Rolontis^®) is a novel long‐acting pegylated recombinant human granulocyte colony-stimulating factor (G-CSF). Eflapegrastim has been developed to reduce the duration and incidence of chemotherapy-induced neutropenia in cancer patients using patient-friendly, less-frequent administration.

Objective

This phase I study aimed to evaluate the safety, tolerability, pharmacokinetic (PK), pharmacodynamic (PD), and immunogenicity of eflapegrastim following a single subcutaneous administration to healthy Japanese and Caucasian subjects.

Methods

A randomized, double-blind, placebo- and active-controlled, dose-escalation study was conducted in healthy Japanese and Caucasian subjects. Eligible subjects randomly received a single subcutaneous administration of eflapegrastim (1.1, 3.3, 10, 45, 135, and 270 μg/kg), pegfilgrastim 6 mg, or placebo in a ratio of 6:2:2 (Cohorts 1–2, Caucasian subjects only) or 12:2:2 (Cohorts 3–6, Japanese and Caucasian subjects). Safety and tolerability were assessed throughout the study. Serial blood samples were collected predose and up to day 22 postdose for PK and PD analyses. PK assessments were performed in the 45, 135, and 270 µg/kg dose groups. Antidrug antibodies to eflapegrastim were determined at baseline up to day 42 after the first dose for immunogenicity.

Results

A total of 84 subjects (42 males and 42 females) were enrolled, and 78 (31 Japanese and 47 Caucasian subjects) completed the study as planned. Japanese and Caucasian subjects showed similar PK and PD profiles. In the 45, 135, and 270 µg/kg dose groups, the maximum serum concentration (C_max) of eflapegrastim exhibited a dose-proportional increase, whereas its exposure increased greater than dose proportional in both ethnic groups. The mean area under the effect-time curve (AUEC_last) and maximum serum concentration of both absolute neutrophil count (ANC_max) and CD34⁺ cell count (CD34⁺_max) increased in a dose-dependent manner. There were no significant adverse events attributable to eflapegrastim or pegfilgrastim in both Japanese and Caucasian subjects. No neutralizing antibodies against G‐CSF were detected.

Conclusions

Eflapegrastim was safe and well tolerated at doses up to 270 μg/kg in healthy Japanese and Caucasian subjects. In both ethnic groups, eflapegrastim showed dose-dependent PK and the exposure to eflapegrastim was positively correlated with ANC and CD34⁺ cell count. The comparable PK and PD profiles of eflapegrastim in Japanese and Caucasian subjects may indicate the same dosage regimen is acceptable.

Clinical Trial Registration

ClinicalTrials.gov: NCT01037543 (23 December 2009).

Prophylaxis and treatment strategies for optimizing chemotherapy relative dose intensity

INTRODUCTION

A decrease in relative-dose intensity (RDI) of chemotherapy has been shown to be associated with poor patient outcomes in solid tumors and non-Hodgkin's lymphoma. The actual delivered chemotherapy dose received by patients can be influenced by dose reductions and treatment delays, often due to toxicities, most commonly chemotherapy-induced neutropenia (CIN).

AREAS COVERED

We review seminal evidence and more recent studies that have shown an association between higher RDI and improved patient survival. A smaller number of studies has shown no association between RDI and outcomes. These differences may be due to study limitations, including low power, differences in patient and disease characteristics, or the chemotherapeutic regimen. We describe guidelines recommendations to prevent and treat CIN with granulocyte-colony stimulating factor (G-CSF) and describe novel approaches to prevent neutropenia that are being developed that may provide greater value and be associated with fewer adverse events than standard G-CSF options.

EXPERT OPINION

Maintaining RDI is important to ensure optimal patient outcomes. This can be achieved through the proper administration of G-CSF prophylaxis and treatment. Newer agents in development to treat and/or prevent CIN are entering regulatory review and may potentially change the treatment landscape for CIN in the future.