ベスト 早期がん検出と液体生検株式 (9月 2026)

最後の大きな殺し手 – がん

Over the last decades, modern medicine has accomplished miracles. Infectious diseases previously killed more people than any other cause, including old age.  The COVID pandemic taught us that this fight is still not over, but we are getting there with new technologies.  Still, another killer is very much active: Cancer.

1990年以降、がんの年齢調整死亡率は約19％しか減少していません。現在、85歳未満の人々にとって主要な死因となっています。

出典: Ark Invest

がんは年齢に関係なく、明確な理由なく発症することがあるため、認知症やアルツハイマー病などよりもはるかに恐ろしく、破壊的です。いくらかの進歩は見られるものの、依然として致命的です。

治療は概ね粗雑で、膨大な量の有毒化学物質を使用したり、体の部位を放射線で照射したりします。

がんの独自性

Calling cancer a disease obfuscates what it really is. Most diseases are either infectious or caused by a single internal dysfunction. But cancer is more like a thousand different diseases stamped with the same label.

がんは体内の1つの細胞が異常になることから始まります。その遺伝子プログラムの「バグ」が急速に変異・増殖し、やがて正常機能がすべて停止し、制御不能に増殖します。止められなければ、臓器全体を支配し死に至ります。

つまり、がんはすべてがユニークです。各がんは異なる「バグ」から生じます。これらのエラーは爆発的増殖段階に至るまでほとんど目立ちません。そしてその時には手遅れになる可能性があります。

したがって、現代医療でがんを検出するということは、健康な細胞ががん化する原因となる何千もの変異を検出することを意味します。

早期発見の重要性

Finding cancer early is absolutely vital. For a long time, the only way to find cancer was through direct observation: scanners, MRI, and direct biopsy (cutting off a little part of the organ suspected to harbor cancerous cells).

これらの方法は精度や感度が不十分（スキャナー、MRI）か、侵襲性が高すぎて（生検）日常的に実施できませんでした。主に乳がんなど特定リスクに対してのみ有効でした。

がん検出の課題は特に深刻です。COVID-19とロックダウン以降、腫瘍科受診が減少しています。

出典: Ark Invest

新たなステップはがん「マーカー」の検出です。ホルモンやその他のバイオプロダクトの異常レベルが対象となります。これにより過去数年で早期検出がわずかに改善しましたが、依然としてがんが臨界サイズに達したときにしか検出できません。

したがって、次のステップは極めて低濃度でがん細胞自体を直接検出することです。

分子がん検出

In biology jargon, the term molecular is generally equivalent to DNA/RNA. This method specifically detects cancer abnormal genetic sequences, or ctDNA (circulating tumor DNA).

The technology is promising but has been hampered by a few limitations so far:

• 検出閾値が低すぎて、直径1〜2cm未満の腫瘍が検出しにくい。
• より高感度な検出は非侵襲的検査ではなく、直接サンプリング（生検）のみで可能。
• 一度に検出できるがんは1種類だけ。
• 一部のがんはctDNA産生が少なく、検出が困難。

Improvements in technology are bringing hope to change early diagnostic methods radically.

マルチがん早期検出 (MCED)

Detecting multiple cancers at once, from a simple blood sample, is the Holy Grail of oncology (this is why the leader in the field is a company called Grail; more on that below).

この方法は「液体生検」とも呼ばれます。You can read more about MCED on the website of the American Cancer Society and the MCED Consortium。

既に存在しますが、全人口に対して日常的に実施するには高額でした。過去7年間で価格が20〜25倍ほど下がり、さらに低下傾向にあるため、もはや高価ではありません。新しい検査は数千のctDNAを同時にチェックし、感度が10倍以上向上しています。

出典: Ark Invest

同じ手法は寛解の評価にも利用できます。

ctDNAを測定することで、化学療法を受ける患者数を減らし、再発率をわずかにでも低減できます。

出典: Ark Invest

さらに、一部の変異はがん細胞を特定の分子や治療に対して脆弱にします。したがって、新しい検出法は治療選択を改善し、生存率を向上させます。

これらすべてが分子診断市場の爆発的成長をもたらすでしょう。現在は2022年時点で50億ドル規模（$5B）の市場ですが、2030年までに240億ドル（$24B）に拡大し、総アドレス可能市場（TAM）は950億ドル（$95B）に達すると予測されています。

出典: Ark Invest

トップ液体生検 株式

1. Grail / Illumina

ILMN 価格チャート

Thanks to its Galleri cancer detection kit, Grail is the leader of the liquid biopsy technology, with a massive 140,000-participant clinical trial underway in the UK and is already available in the US.

Grail is currently part of Illumina, but this is complicated. Grail has spun off from Illumina in 2016. It then raised more money, improved its technology, and was re-acquired by Illumina in 2021 for $7.1B, a lot more than it was spun off for.

And the story does not stop there. You see, Illumina is the leading manufacturer of genetic sequencers, so it is actually providing the required machinery to ALL of Grail’s potential competitors.

So, competition regulators were not happy with Illumina’s 2021 purchase of Grail. They wanted to stop it in the US and the EU, and Illumina ignored the criticism.

Most recently, on 2023年4月3日, the FTC (Federal Trade Commission) ordered Illumina to divest Grail.

“Finally, the Opinion rejects parties’ claim that this acquisition is likely to yield results that save lives, noting that their efficiency projections were vague, self-serving, and unsupported. Ultimately, the Opinion holds that letting competition spur through innovation among MCED test providers would do more to save lives than allowing a monopolist to vertically integrate and capture the market.

This Opinion and Order will now become final unless Respondents file a petition for review in a federal Court of Appeals within 60 days from the date of the service of this Order.”

Illumina’s embattled management has even dealt with the notorious Carl Icahn, the legendary activist investor, who criticized Grail’s acquisition.

So, while technically the most advanced, Grail is not the most straightforward option for investors.

Illumina shareholders might receive shares of Grail, but the details of such a deal, with lawsuits and counter-lawsuits with the FTC, could get messy before it is clear what the future corporate structure of Grail will be.

Illumina getting fined some serious money for its contempt of regulators’ opinion is also a distinct possibility.

2. Exact Sciences Corporation

Exact Sciences is using both DNA & RNA data to detect early cancer, which “simple” DNA tests might miss.

The company develops solutions for all the stages of cancer detection

出典: Exact Sciences

It is also working on a new MCED test, which checks for 4 different biomarker classes simultaneously (DNA, RNA, proteins, methylation).

The company’s R&D efforts paid off, with revenue rising x5 since 2018. It is also worth noticing that the company showed a positive EBITDA for the first time in Q4 2022.

出典: Exact Sciences

Exact Sciences seems like a good option for investors looking at profitable companies in early-stage cancer detection, with an equally good shot at developing an MCED test to compete with Grail. And without all the FTC orders and corporate complexity of Illumina.

3. Natera, Inc.

NTRA 価格チャート

Natera relies on cell-free DNA testing (cfDNA) for women’s health (embryo testing, hereditary cancers), oncology (tumor panel, early detection, residual disease test), and organ testing (kidney, heart, lung).

出典: Natera

The company also sees significant potential for this technology for transplant testing, with only a 10-15% market penetration.

Natera has experienced aggressive growth, with the number of tests growing by 20%-53% every year since 2017, from half a million to 2.1 million tests in 2022.

It is also worth noticing that Natera has been really active in oncology only since 2020. Since 30% of oncologists have ordered their ctDNA residual disease test, Signatera has been an impressive clinical and commercial success.

Natera seems well positioned for Medicare and other public health programs to start pushing for more molecular testing and reimburse them better.

The company plans for 2023 revenue to be 25% higher than 2022’s, with stable R&D and operating expenses. This should still not be enough to reach profitability but would reduce the cash burn by $150M, to the $300M-$325M levels.

Investors in the company will need to pay a close eye on the company’s ability to reach profitability in 2024-2025. The potential threat of more innovative cancer screening tests, like MCED, should also not be ignored.

4. Guardant Health, Inc.

GH 価格チャート

Guardant has developed a liquid biopsy test relying on ctDNA and methylation detection, Guardant Shield.

It also works on complete genomic testing for advanced cancer, allowing for custom therapies/precision medicine. Guardant 360 Cdx is the first FDA-approved blood test for complete genomic testing.

Lastly, Guardant Reveal uses ctDNA to detect early possible cancer recurrence, the “first liquid-only test to detect minimal residual disease (MRD) in colo-rectal cancer, now available for breast and lung cancers.”

出典: Guardant

The next step for Guardant is unifying all its tests under the Smart Liquid Biopsy platform. Most importantly, it will significantly boost the performance of the Guardant Reveal testing, with the company calling it “a larger blockbuster franchise in its early innings.”

出典: Guardant

It is also working on a multi-cancer test, with hopes to submit it for FDA approval in 2026.

Investors should closely follow the growth of the existing product sales and the multi-cancer test clinical trials. Another close eye should be kept on free cash flow, with still negative FCF forecasted in 2025.

出典: Guardant

その他の企業

Other companies, which are not publicly listed, are equally active in making cancer detection as cheap, non-invasive, and powerful as possible.

Notably, Owlstone Medical developed “Breath Biopsy,” which can detect cancer or other diseases from a breath sample.

And Adela, studying the DNA-methylome for early cancer detection.

All in all, this extremely active sector of liquid biopsy is likely to make cancer a lot more survivable and detecting it a part of our routine health checks.