HER2低発現転移性乳がん（mBC）市場：1次調査（KOLの洞察） - 市場インテリジェンス - 疫学と2034年までの市場予測

HER2低発現転移性乳がん（mBC）市場は、化学療法、内分泌療法、トラスツズマブ・デルクステカン（Enhertu）などの標的療法が大きく貢献しています。2034年までに、新規の新興治療薬の取り込みが、HER2-低転移性乳がん治療薬市場に劇的な変化をもたらす主要なブレークポイントとなるでしょう。調査対象国（米国、フランス、ドイツ、イタリア、スペイン、英国、日本）におけるHER2低発現転移性乳がん治療用の新興治療薬の売上は、2020年～2034年の調査期間中に高い成長を遂げると予測されています。

HER2低発現転移性乳がんの治療法は急速に進化しているとみられています。最近の臨床試験では、CDK4/6阻害剤と内分泌療法の併用が標準的な一次治療として有効であることが実証されています。さらに、PI3K阻害剤やAKT阻害剤の使用も臨床試験で検討されており、近い将来、さらなる治療選択肢を提供する可能性があります。"

HER2低発現転移性乳がんは、乳がんの理解と治療における大きな転換を意味します。歴史的に、乳がんはHER2発現レベルに基づいてHER2陽性またはHER2陰性に分類されていました。しかし、現在では乳がんの50％以上が「ヒト上皮成長因子受容体2（HER2）低発現乳がん（BC）」と定義されており、HER2免疫組織化学（IHC）スコアが＋1または＋2であり、蛍光in situハイブリダイゼーション（FISH）検査が陰性です。IHC/ISHは、HER2発現を定義するために現在適用されている唯一の標準的技術です。最近のエビデンスでは、HER2低発現乳がんは治療的意義のある標的サブグループになり得ることが示唆されています。

G7諸国におけるHER2低発現転移性乳がんの総発生症例数は、2034年までに相当数増加すると予測されます。推計によると、2034年には米国がHER2低発現転移性乳がん症例の発生率が最も高くなります。EU5の中では、ドイツが最もHER2低発現転移性乳がん症例数が多く、英国、フランス、イタリア、スペインがこれに続く。日本は米国、ドイツ、英国に次いで治療症例数が多いと報告されています。

SEERデータベースによると、米国では2022年に新たに287,850例の女性乳がんが診断されると推定されており、新たに乳がんと診断された患者のうち、約50～60％がHER2低発現転移性乳がんと診断されています。

HER2低発現転移性乳がん治療薬市場は、調査期間中（i.e.2020年から2034年まで）高成長が見込まれています。米国が欧州5カ国および日本と比較して最も高い市場シェアを獲得しています。

当レポートでは、世界のHER2低発現転移性乳がん（mBC）市場について調査し、市場の現状とともに、症例数の動向、患者動向、競合製品の市場における位置づけ、市場の機会などを提供しています。

目次

エグゼクティブサマリー

HER2低転移性乳がん疾患の背景

• HER2-低転移性乳がんの定義
• 原因と症状
• 病態生理学
• 乳がんにおけるHER2の低発現に寄与する因子

HER2低転移性乳がんの診断

疫学と患者集団

• 主な調査結果
• メソッドとデータソース
• HER2低転移性乳がんの疫学とモデルパラメータの主要な情報源
  • 米国
  • ドイツ
  • フランス
  • イタリア
  • スペイン
  • 英国
  • 日本
• 現在の治療法と医療行為
  • 市販療法
  • アンメットニーズ
  • 新しい治療法
  • 製品分析
  • 発売スケジュールと主な市場イベント
  • 価格と償還
  • KOLの洞察（米国、欧州、日本）
  • 将来の治療パラダイム
  • 現在および今後の治療の年間コスト
  • HER2低転移性乳がんにおける後期治療の戦略的考慮事項
  • 市場の見通し
  • 主要医薬品市場におけるHER2-低転移性乳がん治療薬の売上高（2020年～2034年）
  • 治療法別のHER2低転移性乳がんの患者割合
• 国別市場予測
  • 米国
  • ドイツ
  • フランス
  • スペイン
  • 英国
  • 日本
• 市場促進要因と抑制要因
• 付録

The HER2-Low Metastatic Breast Cancer (mBC) market is hugely contributed by chemotherapy, endocrine therapy and targeted therapy such as Trastuzumab deruxtecan (Enhertu). By 2034, the uptake of novel emerging therapies will serve as a major breakpoint to get a drastic change in the HER2-Low Metastatic Breast Cancer therapeutics market. The sales of the emerging therapies for the treatment of HER2-Low Metastatic Breast Cancer in the study countries (United States, France, Germany, Italy, Spain, United Kingdom and Japan) will experience high growth over the 2020-2034 study period.

"Experts believe that the treatment armamentarium for HER2-low metastatic breast cancer is rapidly evolving. Recent clinical trials have demonstrated the efficacy of CDK4/6 inhibitors in combination with endocrine therapy as a standard first-line treatment option. Additionally, the use of PI3K inhibitors and AKT inhibitors is being explored in clinical trials and may provide further treatment options in the near future."

The introduction of HER2-low metastatic breast cancer represents a significant shift in the understanding and treatment of breast cancer. Historically, breast cancers were categorized as either HER2-positive or HER2-negative based on the level of HER2 expression. However, more than 50% of breast cancers are currently defined as "Human epidermal growth factor receptor 2 (HER2) low breast cancer (BC)", with HER2 immunohistochemistry (IHC) scores of +1 or +2 with a negative fluorescence in situ hybridization (FISH) test. IHC/ISH is the only standard technique currently applied to define HER2 expression. Recent evidence suggests that HER2-low breast cancer can be a targetable subgroup with potential therapeutic implications.

Mellalta's HER2-Low Metastatic Breast Cancer Report– Market Summary

Report Attributes	Details
Key Market Players:	Jiangsu HengRui Medicine; Duality Biologics; Yantai Rongchang Pharmaceutical; Gilead Sciences; AstraZeneca/Daiichi Sankyo.
Forecast Period:	2020-2034.
Countries Covered:	US, France, Germany, Italy, Spain, UK, China and Japan.
Current SOC:	Chemotherapy; Endocrine Therapies; Targeted Therapies.
Future SOC:	Targeted Therapies; Combination Approach.
Key Unmet Need:	Improved HER2 Assessment; Limited Treatment Option.
Key Clinical Insights:	Emergence of HER2-low breast cancer has led to a significant change in treatment algorithms for patients with breast cancer. The introduction of targeted therapies like T-DXd offers new treatment options for patients who were previously considered to have limited options.
Provider-Patient (PPP) Perspective:	Cost-effectiveness of treatment; Better Diagnostic Identification; Access to appropriate treatments and improved options.

Mellalta's HER2-Low Metastatic Breast Cancer Report – Epidemiology

The total incident cases of HER2-Low Metastatic Breast Cancer in the G7 countries are anticipated to increase by a significant number of cases by 2034 for the study period (2020-2034). As per estimates, the United States will present with the highest incidence of HER2-Low Metastatic Breast Cancer cases in 2034. Among the EU5, Germany had the highest HER2-Low Metastatic Breast Cancer cases, followed by the UK, France, Italy, and Spain. Japan is reported to have the highest number of treated cases after the United States, Germany, and the UK.

According to SEER database estimates 287,850 new cases of female breast cancer will be diagnosed in 2022 in the U.S. Out of the newly diagnosed breast cancer patient, roughly 50-60% of patients is now diagnosed with HER2 Low metastatic Breast Cancer.

Mellalta's HER2-Low Metastatic Breast Cancer Report – Current Market Size & Forecast Trends

The HER2-Low Metastatic Breast Cancer therapeutics market is expected to experience high growth throughout our study period (i.e., 2020 to 2034). The United States captured the highest market share as compared to the European 5 countries and Japan.

The current standard of care is limited to chemotherapy, endocrine and targeted therapy. In 2022, Enhertu (fam-trastuzumab-deruxtecan-nxki), an IV infusion is approved as the first targeted therapy for the treatment of patients with unresectable or metastatic HER2-low breast cancer in the United States and in 2023 in the European Union. This shift in treatment options has significant implications for the market. The changing treatment landscape has created new opportunities in the market for more companies to develop and commercialize the use of ADCs in HER2-low tumours. Additionally, the entrance of ADCs like Enhertu in the treatment paradigm of HER2-low breast cancer will also pave the way for diagnostic companies to develop the specific test for the identification of HER2-low breast cancer patient pool, which will be in turn increase the treated patient pool and will drive the market of HER2 low breast cancer significantly.

While the results of DESTINY-Breast04 study led to the breakthrough approval of Enhertu in the HER2 low breast cancer treatment space, it also changed the prescribing pattern among clinician's posing significant obstacles. These challenges include raising clinician awareness through education, updating practice guidelines, managing increasing treatment complexity, and addressing a lack of data surrounding the complex characteristics and temporal heterogeneity of HER2-low tumors.

In the 2024-2034 forecast period, there will be tremendous growth and shift in the therapeutic market with the launch of noble emerging therapies like Trastuzumab rezetecan (Jiangsu HengRui Medicine), DB-1303 (Duality Biologics), Disitamab vedotin (Yantai Rongchang Pharmaceutical), Sacituzumab Govitecan (Gilead Sciences), Datopotamab deruxtecan (AstraZeneca/Daiichi Sankyo), MRG002 (Miracogen), and more. We expect a greater uptake of the new therapies which will result in better treatment outcomes for HER2-Low Metastatic Breast Cancer market space. The launch of these upcoming therapies will drive the highly competitive therapeutic market in the coming time.

Questions Answered:

• What is the size of clinically and commercially relevant drug-treatable HER2 low BC populations, and how will drug-treatment rates of HER2 change over time?
• What is the expected market impact of recent drug approval such as Enhertu in the treatment landscape of HER2-low metastatic BC?
• Potential challenges and opportunities in implementing targeted therapies for HER2-low breast cancer.
• What are the most promising agents in the pipeline, and how will they shape the future of this therapy market?
• What key drivers and constraints will affect the HER2-low metastatic breast cancer therapy market over the forecast period?

Report Highlights:

• HER2-Low Metastatic Breast Cancer (mBC) – Current Market Trends
• HER2-Low Metastatic Breast Cancer (mBC) – Current & Forecasted Cases across the G7 Countries
• HER2-Low Metastatic Breast Cancer (mBC) – Market Opportunities and Sales Potential for Agents
• HER2-Low Metastatic Breast Cancer (mBC) – Patient-based Market Forecast to 2034
• HER2-Low Metastatic Breast Cancer (mBC) – Untapped Business Opportunities
• HER2-Low Metastatic Breast Cancer (mBC) – Product Positioning Vis-a-vis Competitors' Products
• HER2-Low Metastatic Breast Cancer (mBC) – KOLs Insight

Table of Content

Executive Summary

• Key Findings
• Key Market Challenges and Opportunities
• What Do the Experts Say?

HER2-Low Metastatic Breast Cancer Disease Background

• HER2-Low Metastatic Breast Cancer Definition
• Cause & Symptoms
• Pathophysiology
• Factors contributing to the HER2-Low Expression in Breast Cancer

HER2-Low Metastatic Breast Cancer–Diagnosis

• HER2 Assessment with Immunohistochemistry (IHC) and In Situ Hybridization (ISH) (ASCO/CAP Guidelines)

Epidemiology and Patient Populations

• Key Findings
• Methods and data Sources
  • Country Specific Incident cases of Metastatic Breast Cancer (US, Germany, France, Italy, Spain, UK, and Japan)
  • Country Specific Incident cases of HER2-Low Metastatic Breast Cancer
  • Country Specific Treated cases of HER2-Low Metastatic Breast Cancer
• Key Sources for HER2-Low Metastatic Breast Cancer Epidemiology and Model Parameters
  • United States
    • United States Incident cases of Metastatic Breast Cancer (US, Germany, France, Italy, Spain, UK, and Japan)
    • United States Incident cases of HER2-Low Metastatic Breast Cancer
    • United States Treated cases of HER2-Low Metastatic Breast Cancer
  • Germany
    • Germany Incident cases of Metastatic Breast Cancer (US, Germany, France, Italy, Spain, UK, and Japan)
    • Germany Incident cases of HER2-Low Metastatic Breast Cancer
    • Germany Treated cases of HER2-Low Metastatic Breast Cancer
  • France
    • France Incident cases of Metastatic Breast Cancer (US, Germany, France, Italy, Spain, UK, and Japan)
    • France Incident cases of HER2-Low Metastatic Breast Cancer
    • France Treated cases of HER2-Low Metastatic Breast Cancer
  • Italy
    • Italy Incident cases of Metastatic Breast Cancer (US, Germany, France, Italy, Spain, UK, and Japan)
    • Italy Incident cases of HER2-Low Metastatic Breast Cancer
    • Italy Treated cases of HER2-Low Metastatic Breast Cancer
  • Spain
    • Spain Incident cases of Metastatic Breast Cancer (US, Germany, France, Italy, Spain, UK, and Japan)
    • Spain Incident cases of HER2-Low Metastatic Breast Cancer
    • Spain Treated cases of HER2-Low Metastatic Breast Cancer
  • United Kingdom
    • United Kingdom Incident cases of Metastatic Breast Cancer (US, Germany, France, Italy, Spain, UK, and Japan)
    • United Kingdom Incident cases of HER2-Low Metastatic Breast Cancer
    • United Kingdom Treated cases of HER2-Low Metastatic Breast Cancer
  • Japan
    • Japan Incident cases of Metastatic Breast Cancer (US, Germany, France, Italy, Spain, UK, and Japan)
    • Japan Incident cases of HER2-Low Metastatic Breast Cancer
    • Japan Treated cases of HER2-Low Metastatic Breast Cancer
• Current Therapy and Medical Practice
  • Key Findings
  • Treatment Algorithm
  • Marketed Therapy
    • ENHERTU (AstraZeneca/Daiichi Sankyo)
      • Product Profile
      • Clinical Development
      • Market & Sales Opportunity Forecasted to 2034
  • Unmet Needs
  • Emerging Therapy
    • Key Findings
    • Pipeline Overview
    • Notable Developments in the HER2-Low Metastatic Breast Cancer space
      • Product Analysis
        • Trastuzumab rezetecan (Jiangsu HengRui Medicine)
          • Product Profile
          • Clinical Development
          • Market & Sales Opportunity Forecasted to 2034
        • DB-1303 (Duality Biologics)
          • Product Profile
          • Clinical Development
          • Market & Sales Opportunity Forecasted to 2034
        • Disitamab vedotin (Yantai Rongchang Pharmaceutical)
          • Product Profile
          • Clinical Development
          • Market & Sales Opportunity Forecasted to 2034
        • Sacituzumab Govitecan (Gilead Sciences)
          • Product Profile
          • Clinical Development
          • Market & Sales Opportunity Forecasted to 2034
        • Datopotamab deruxtecan (AstraZeneca/Daiichi Sankyo)
          • Product Profile
          • Clinical Development
          • Market & Sales Opportunity Forecasted to 2034
        • MRG002 (Miracogen)
          • Product Profile
          • Clinical Development
          • Market & Sales Opportunity Forecasted to 2034
        • Others
  • Launch Timeline & Key Market Events for HER2-Low Metastatic Breast Cancer
  • HER2-Low Metastatic Breast Cancer – Pricing & Reimbursement
  • KOLs Insight (US, EU, JP)
    • Unmet Needs
    • Analysis of the progresses in terms of approvals & current pipeline;
    • Impact on the treatment algorithm and product positioning
    • Relevance of new targets/platforms/ therapies Uptake Share %
    • Physicians Preferences for the new therapies
  • Future Treatment Paradigm
    • HER2-Low Metastatic Breast Cancer Competitor Landscape and Approvals Anticipated
    • Future Treatment Algorithms and Competitor Positioning
    • Key Data Summary for Emerging Treatment
  • Annual Cost of Current & Emerging Treatment
  • Late Phase Therapy Strategic Considerations in HER2-Low Metastatic Breast Cancer
  • Market Outlook
    • Key Findings
    • Overview
    • Country Specific Market Forecast to 2034
      • Sales of Drugs to Treat HER2-Low Metastatic Breast Cancer in the Major Pharmaceutical Markets, 2020-2034
      • Patient Share of HER2-Low Metastatic Breast Cancer by Therapies
    • Market Forecast by Country
      • United States
        • United States Market for HER2-Low Metastatic Breast Cancer 2020-2034 (USD Million)
        • United States Market for HER2-Low Metastatic Breast Cancer by Therapy 2020-2034 (USD Million)
      • Germany
        • Germany Market for HER2-Low Metastatic Breast Cancer 2020-2034 (USD Million)
        • Germany Market for HER2-Low Metastatic Breast Cancer by Therapy 2020-2034 (USD Million)
      • France
        • France Market for HER2-Low Metastatic Breast Cancer 2020-2034 (USD Million)
        • France Market for HER2-Low Metastatic Breast Cancer by Therapy 2020-2034 (USD Million)
      • Italy • Italy Market for HER2-Low Metastatic Breast Cancer 2020-2034 (USD Million) • Italy Market for HER2-Low Metastatic Breast Cancer by Therapy 2020-2034 (USD Million)
      • Spain
        • Spain Market for HER2-Low Metastatic Breast Cancer 2020-2034 (USD Million)
        • Spain Market for HER2-Low Metastatic Breast Cancer by Therapy 2020-2034 (USD Million)
      • United Kingdom
        • United Kingdom Market for HER2-Low Metastatic Breast Cancer 2020-2034 (USD Million)
        • United Kingdom Market for HER2-Low Metastatic Breast Cancer by Therapy 2020-2034 (USD Million)
      • Japan
        • Japan Market for HER2-Low Metastatic Breast Cancer 2020-2034 (USD Million)
        • Japan Market for HER2-Low Metastatic Breast Cancer by Therapy 2020-2034 (USD Million)
  • Market Drivers and Constraints
    • What Factors Are Driving the Market for HER2-Low Metastatic Breast Cancer?
    • What Factors Are Constraining the Market for HER2-Low Metastatic Breast Cancer?
  • Appendix
    • Methodology