MedPath

Leucovorin

Generic Name
Leucovorin
Brand Names
EnBrace HR, EnLyte, Lederle Leucovorin
Drug Type
Small Molecule
Chemical Formula
C20H23N7O7
CAS Number
58-05-9
Unique Ingredient Identifier
Q573I9DVLP
Background

Folinic Acid (also known as 5-formyl tetrahydrofolic acid or leucovorin) is the 5-formyl derivative of tetrahydrofolic acid, a necessary co-factor in the body. Commercially available leucovorin is composed of a 1:1 racemic mixture of the dextrorotary and levorotary isomers, while levoleucovorin contains only the pharmacologically active levo-isomer. In vitro, the levo-isomer has been shown to be rapidly converted to the biologically available methyl-tetrahydrofolate form while the dextro form is slowly excreted by the kidneys. Despite this difference in activity, the two commercially available forms have been shown to be pharmacokinetically identical and may be used interchangeably with limited differences in efficacy or side effects (Kovoor et al, 2009).

As folate analogs, leucovorin and levoleucovorin are both used to counteract the toxic effects of folic acid antagonists, such as methotrexate, which act by inhibiting the enzyme dihydrofolate reductase (DHFR). They are indicated for use as rescue therapy following use of high-dose methotrexate in the treatment of osteosarcoma or for diminishing the toxicity associated with inadvertent overdosage of folic acid antagonists. Injectable forms are also indicated for use in the treatment of megaloblastic anemias due to folic acid deficiency when oral therapy is not feasible and for use in combination with 5-fluorouracil to prolong survival in the palliative treatment of patients with advanced colorectal cancer.

Folic acid is an essential B vitamin required by the body for the synthesis of purines, pyrimidines, and methionine before incorporation into DNA or protein. However, in order to function in this role, it must first be reduced by the enzyme dihydrofolate reductase (DHFR) into the cofactors dihydrofolate (DHF) and tetrahydrofolate (THF). This important pathway, which is required for de novo synthesis of nucleic acids and amino acids, is disrupted when high-dose methotrexate is used for cancer therapy. As methotrexate functions as a DHFR inhibitor to prevent DNA synthesis in rapidly dividing cells, it also prevents the formation of DHF and THF. This results in a deficiency of coenzymes and a resultant buildup of toxic substances that are responsible for numerous adverse side effects associated with methotrexate therapy. As levoleucovorin and leucovorin are analogs of tetrahydrofolate (THF), they are able to bypass DHFR reduction and act as a cellular replacement for the co-factor THF, thereby preventing these toxic side effects.

Indication

For the treatment of osteosarcoma (after high dose methotrexate therapy). Used to diminish the toxicity and counteract the effects of impaired methotrexate elimination and of inadvertent overdosages of folic acid antagonists, and to treat megaloblastic anemias due to folic acid deficiency. Also used in combination with 5-fluorouracil to prolong survival in the palliative treatment of patients with advanced colorectal cancer.

Associated Conditions
Advanced Colorectal Cancer, Advanced Esophageal Cancers, Anemia of Pregnancy, Bladder Cancer, Folate and iron deficiency, Folate deficiency, Folic acid antagonist overdose, Iron Deficiency (ID), Macrocytic anemia, Megaloblastic anemia, Pancreatic Metastatic Cancer, Postpartum Anemia, Stage IV Gastric Cancer, Hypochromic anemia, Methotrexate toxicity, Normochromic anemia, Pyrimethamine hematologic toxicity

Merck and Daiichi Sankyo Launch Phase 3 Trial of Novel B7-H3 Targeted ADC for Advanced Esophageal Cancer

• The IDeate-Esophageal01 Phase 3 trial has begun evaluating ifinatamab deruxtecan, a potential first-in-class B7-H3 directed antibody-drug conjugate, against standard chemotherapy in advanced esophageal squamous cell carcinoma. • Esophageal squamous cell carcinoma accounts for 90% of global esophageal cancers with dismal survival rates of 15-20%, highlighting the urgent need for new treatment approaches after first-line therapy failure. • The trial follows promising early-phase results and will enroll approximately 510 patients across Asia, Europe, and North America, with overall survival as the primary endpoint.

TFOX Regimen Shows Superior Efficacy Over FOLFOX in Advanced HER2-Negative Gastric Cancer

• French phase III PRODIGE 51-FFCD-GASTFOX trial demonstrates modified FLOT regimen (TFOX) significantly improves progression-free and overall survival compared to FOLFOX in advanced HER2-negative gastric cancer. • The TFOX regimen achieved a median overall survival of 15.1 months versus 12.7 months with FOLFOX, along with higher objective response rates (62.3% vs 53.4%) despite increased toxicity. • Researchers suggest TFOX represents a promising new first-line treatment option for patients eligible for docetaxel triplet chemotherapy, particularly those under 70 with good performance status.

HAIC with FOLFOX Plus Camrelizumab and Sorafenib Shows Limited Efficacy in Advanced HCC

• A phase II trial investigating hepatic artery infusion of FOLFOX chemotherapy plus camrelizumab combined with sorafenib in BCLC stage C hepatocellular carcinoma failed to meet its primary endpoint, showing a modest 44% objective response rate. • The treatment demonstrated a manageable safety profile with grade ≥3 treatment-related adverse events in 76% of patients, primarily including decreased lymphocyte count (52%) and elevated liver enzymes (44%). • In contrast, a separate trial combining HAIC with camrelizumab and apatinib as conversion therapy for unresectable HCC showed promising results with a 73.7% conversion rate and 47.4% R0 resection rate.

Infinitopes Secures MHRA Approval for Phase I/IIa Trial of Novel Cancer Vaccine Against Oesophageal Adenocarcinoma

• Infinitopes has received UK MHRA approval for a first-in-human Phase I/IIa clinical trial of ITOP1, an 'off-the-shelf' precision cancer vaccine designed to prevent recurrence in patients with surgically resectable oesophageal adenocarcinoma. • The VISTA study will enroll 60 patients across four UK cancer centers, administering ITOP1 in a prime/boost regimen alongside standard FLOT chemotherapy, with the trial set to commence in Q2 2025. • ITOP1 leverages AI/ML-driven immunopeptidomics to target tumor antigens with high specificity, activating CD8+ cytotoxic T cells to eliminate residual cancer cells and potentially revolutionize treatment for oesophageal cancer, which claims 8,500 lives annually in the UK.

Chemotherapy Plus Local Excision Shows Promise for Node-Negative Low Rectal Cancer Patients

• Fox Chase Cancer Center researchers found that neoadjuvant chemotherapy followed by local excision achieved negative margins in 79% of patients with node-negative low rectal cancer, potentially avoiding permanent colostomies. • The phase II trial demonstrated a 31% pathologic complete response rate with no local recurrences at a median follow-up of 26 months, while maintaining patients' quality of life and bowel function. • This organ-preserving approach could offer a less invasive alternative to total mesorectal excision for select rectal cancer patients, with shorter recovery times and fewer side effects.

Immunotherapy in Gastric Cancer: Moving to Earlier Disease Stages and Optimizing Combination Approaches

• Leading oncologist Dr. Yelena Janjigian emphasizes the need to advance immunotherapy to earlier disease stages in gastric, GEJ, and esophageal cancers, with promising data expected from the MATTERHORN study. • Recent evidence from phase 3 trials TOPGEAR and ESOPEC demonstrates that radiation therapy does not improve survival outcomes in gastric/GEJ cancers, challenging conventional treatment approaches. • FLOT chemotherapy regimen combined with durvalumab represents an optimal treatment strategy for the perioperative setting, addressing the systemic nature of gastric cancer rather than focusing on localized radiation therapy.

Isofol Medical Advances Arfolitixorin Development with New Phase Ib/II Trial for Metastatic Colorectal Cancer

• Isofol Medical has received regulatory approval to initiate a Phase Ib/II clinical trial evaluating arfolitixorin in first-line treatment of metastatic colorectal cancer at Germany's prestigious Charité Universitätsmedizin Berlin. • The new study implements an optimized dosing regimen with higher doses administered earlier in the treatment cycle, designed to enhance arfolitixorin's synergistic effects with 5-FU chemotherapy. • The trial will replace leucovorin with arfolitixorin in standard treatment protocols and will be conducted in two stages: dose escalation assessment followed by efficacy comparison between selected dosages.

OSE2101 Cancer Vaccine Shows Promising Results in Phase 2 Pancreatic Cancer Trial

• The TEDOPaM Phase 2 trial met its primary endpoint, demonstrating that OSE2101 (Tedopi) combined with FOLFIRI chemotherapy achieved a statistically significant improvement in one-year overall survival rate for advanced pancreatic cancer patients. • The neoepitope-based therapeutic cancer vaccine showed minimal toxicity when used as maintenance therapy in HLA-A2 positive patients who had not progressed after FOLFIRINOX induction chemotherapy. • Researchers emphasize these results provide hope in a difficult-to-treat cancer with low survival rates, though further analysis and longer follow-up are needed to fully understand the vaccine's contribution to the observed benefits.

Triple Combination of Envafolimab, Suvemcitug, and FOLFIRI Shows Promise in Advanced Colorectal Cancer

• Phase 2 trial demonstrates 25% objective response rate and 90% disease control rate in patients with microsatellite stable colorectal cancer treated with envafolimab-suvemcitug-FOLFIRI combination. • The treatment showed manageable safety profile with no treatment discontinuations due to adverse effects, though 90% of patients experienced grade 3 or higher treatment-related events. • Median progression-free survival reached 5.6 months, with particularly encouraging response rates of 36.4% observed in patients with lung metastases.

Pelareorep Plus FOLFIRINOX Shows Acceptable Safety in Metastatic Pancreatic Cancer

• The GOBLET study's safety run-in showed that pelareorep with modified FOLFIRINOX, with or without atezolizumab, is acceptably safe in metastatic pancreatic ductal adenocarcinoma (PDAC). • The combination therapy demonstrated manageable adverse events, consistent with the known safety profiles of the individual drugs, allowing the study to continue full enrollment. • While efficacy results are pending, the safety data supports further investigation of this combination in patients with newly diagnosed metastatic PDAC. • The study continues to enroll patients to evaluate tumor response to pelareorep plus mFOLFIRINOX with or without atezolizumab.

NALIRIFOX Shows Numerically Improved Overall Survival Compared to FOLFIRINOX in Metastatic PDAC

• A real-world study indicated that first-line NALIRIFOX had a numerically higher median overall survival (OS) of 11.1 months compared to FOLFIRINOX's 9.1 months in mPDAC patients. • The analysis included a trial-aligned cohort, an all-comer cohort, and a modified FOLFIRINOX cohort, assessing survival outcomes in metastatic pancreatic ductal adenocarcinoma. • The findings suggest NALIRIFOX may offer a survival advantage over FOLFIRINOX in treating mPDAC, warranting further studies adjusting for baseline characteristics. • Data were sourced from the Flatiron Electronic Health Record, covering patients treated between January 2014 and February 2024, providing a comprehensive real-world view.

Nivolumab Plus Chemotherapy Demonstrates Sustained Survival Benefit in Advanced Gastroesophageal Cancers

• Five-year follow-up data from the CheckMate 649 trial shows nivolumab plus chemotherapy continues to improve overall survival in advanced gastric, GEJ, and esophageal adenocarcinoma patients. • In patients with PD-L1 CPS ≥5, median OS was 14.4 months with nivolumab plus chemotherapy vs 11.1 months with chemotherapy alone, with 5-year OS rates of 16% and 6%, respectively. • Among Chinese patients, nivolumab plus chemotherapy showed a median OS of 14.3 months compared to 10.3 months with chemotherapy alone, reinforcing it as a standard first-line treatment. • The combination therapy maintained a favorable safety profile, with no new safety signals identified during the extended follow-up period.

FDA Approves Sotorasib Plus Panitumumab for KRAS G12C-Mutated Metastatic Colorectal Cancer

• The FDA has approved sotorasib (Lumakras) in combination with panitumumab (Vectibix) for treating KRAS G12C-mutated metastatic colorectal cancer in adults who have received prior chemotherapy. • This approval is based on the Phase 3 CodeBreaK 300 trial, which demonstrated a significant improvement in progression-free survival compared to standard of care. • The combination therapy led to a median progression-free survival of 5.6 months, a substantial increase compared to the 2 months observed with standard treatments. • The FDA also approved the therascreen KRAS RGQ PCR Kit as a companion diagnostic to identify patients eligible for this targeted treatment approach.

Arvinas Advances Vepdegestrant into Phase 3 Trials for Breast Cancer and Updates Pipeline Milestones

• Arvinas plans to initiate two Phase 3 trials in 2025 for vepdegestrant in ER+/HER2- metastatic breast cancer, one in the first-line setting with atirmociclib and another in the second-line setting with a CDK4/6 inhibitor. • Topline data from the Phase 3 VERITAC-2 monotherapy trial of vepdegestrant in second-line-plus ER+/HER2- metastatic breast cancer is anticipated in the first quarter of 2025. • Arvinas is set to present initial data from the Phase 1 trial of ARV-393 in B-cell lymphomas and file an IND application for a novel PROTAC KRAS G12D degrader in 2025. • Phase 1 trial with PROTAC LRRK2 degrader ARV-102 in patients with Parkinson’s disease has been initiated, with data expected to be presented in the first half of 2025.

FDA Grants Priority Review to Astellas' Zolbetuximab for Gastric and GEJ Adenocarcinoma

• The FDA has granted Priority Review to Astellas' Biologics License Application (BLA) for zolbetuximab, a Claudin 18.2-targeted monoclonal antibody. • Zolbetuximab is intended as a first-line treatment for locally advanced or metastatic HER2-negative gastric or gastroesophageal junction (GEJ) adenocarcinoma. • The BLA is supported by positive results from the Phase 3 SPOTLIGHT and GLOW trials, evaluating zolbetuximab in combination with chemotherapy regimens. • The FDA's target action date is set for January 12, 2024, potentially making zolbetuximab the first Claudin 18.2-targeted therapy available in the US.

China NMPA Approves Astellas' Zolbetuximab for Advanced Gastric and GEJ Adenocarcinoma

• China's NMPA has approved zolbetuximab (VYLOY™) for first-line treatment of HER2-negative gastric or gastroesophageal junction (GEJ) adenocarcinoma. • Zolbetuximab is the first monoclonal antibody approved in China that targets the CLDN18.2 biomarker expressed in gastric tumor cells. • Approval was based on Phase 3 GLOW and SPOTLIGHT trials, showing statistically significant improvements in progression-free and overall survival. • Approximately 35% of Chinese patients with advanced gastric and GEJ cancers have tumors expressing the CLDN18.2 biomarker.

Pfizer's Braftovi Combo Shows Survival Benefit in BRAF-Mutated Metastatic Colorectal Cancer

• Pfizer's Braftovi, combined with cetuximab and mFOLFOX6, significantly improved progression-free survival in metastatic colorectal cancer patients with BRAF V600E mutation. • The BREAKWATER trial demonstrated a clinically meaningful improvement in overall survival with the Braftovi regimen compared to chemotherapy. • The FDA granted accelerated approval to the Braftovi combination in December 2024, marking it as a first-line targeted therapy option. • Pfizer plans to share the BREAKWATER data with regulatory authorities to support full approval and broader use of the Braftovi combination.

Camrelizumab and Apatinib Show Promise in Neoadjuvant Treatment of TNBC

• Camrelizumab plus chemotherapy significantly improved pathologic complete response (pCR) rates in early or locally advanced triple-negative breast cancer (TNBC). • Apatinib combined with sintilimab and chemotherapy demonstrated a high pCR rate of 70.6% in early TNBC, suggesting synergistic effects. • Both camrelizumab and apatinib regimens exhibited manageable safety profiles, supporting their potential as new neoadjuvant therapeutic options. • Biomarker analysis in the apatinib study identified correlations between immune response and pCR, offering insights for predicting treatment efficacy.

Biomarker-Guided Therapies Transform Treatment Landscape Across Multiple Cancers

• Recent advances in targeted therapies including KRAS, BRAF, and CLDN18.2 inhibitors are revolutionizing treatment approaches for pancreatic, colorectal, lung and gastric cancers through molecular profiling-guided precision medicine. • Zolbetuximab plus chemotherapy demonstrated significant survival benefits in CLDN18.2-positive gastric cancer, while KRAS inhibitors showed promising response rates of 20-45% in pancreatic cancer patients with specific mutations. • Multiple biomarker-targeted approaches including HER2, PD-L1, and FGFR2 are expanding treatment options across gastrointestinal cancers, though optimal sequencing strategies are still being determined.

Imfinzi Approved for Limited-Stage Small Cell Lung Cancer, Redefining Treatment

• The FDA has approved AstraZeneca's Imfinzi (durvalumab) for treating adults with limited-stage small cell lung cancer (LS-SCLC) after platinum-based chemotherapy and radiation therapy. • The approval was based on the ADRIATIC Phase III trial, which showed a 27% reduction in the risk of death compared to placebo, marking a significant breakthrough. • Median overall survival improved to 55.9 months with Imfinzi versus 33.4 months with placebo, establishing a new benchmark for LS-SCLC treatment. • Imfinzi is now the only immunotherapy approved for both limited and extensive-stage small cell lung cancer, underscoring its potential to improve survival rates.
© Copyright 2025. All Rights Reserved by MedPath