Tag

Tagged: immunotherapy drugs

5 years, 9 months ago

45134
0
Facebook

Twitter

Google+

LinkedIn

Report

AstraZeneca’s strategy to target early cancer

HealthPad

Directory:

Cancer

Tags:

pharmaceutical companies

R&D

AstraZeneca has turned traditional biopharma R&D on its head and is targeting early stage cancer
This strategy benefits from some of AstraZeneca’s R&D endeavours
But the strategy faces strong headwinds, which include significant technological and market challenges and substantial Competition from at least two unicorns

AstraZeneca’s strategy to target early cancer

Will José Baselga’s gamble pay off?

Baselga is AstraZeneca's new cancer research chief who has turned traditional biopharmaceutical drug development on its head by announcing AstraZeneca’s intention to target early- rather than late-stage cancer. “We need to spend our resources on those places where we can cure more people and that’s in early disease”, says Baselga, who knows that early detection can significantly improve patient survival rates and quality of life, as well as substantially reducing the cost and complexity of cancer treatment. Baselga also must know his strategy is high risk. Will it work?

In this Commentary

In this Commentary we discuss the drivers and headwinds of AstraZeneca’s strategy to increase its R&D focus on early stage cancer. But first we briefly describe cancer, the UK’s situation with regard to the disease and explain why big pharma targets advanced cancers. Also, we provide a brief description of AstraZeneca’s recent history.

What is cancer?

Cancer occurs when a normal cell’s DNA changes and multiplies to form a mass of abnormal cells, which we refer to as a tumour. If not controlled and managed appropriately the tumour can spread and invade other tissues and organs. In the video below Whitfield Growdon, a surgical oncologist at the Massachusetts General Hospital in Boston US, and a Professor at the Harvard University Medical School explains.

The UK’s record of cancer treatment

In the UK cancer survival rates vary between types of the disease, ranging from 98% for testicular cancer to just 1% for pancreatic cancer. Although the UK’s cancer survival rates lag those of other European countries, the nation’s overall cancer survival rate is improving. Several cancers are showing significant increases in five-year survival, including breast (80% to 86%), prostate (82% to 89%), rectum (55% to 63%) and colon (52% to 60%). Many of the most commonly diagnosed cancers in the UK have ten-year survival of 50% or more. With regard to cancer spending, compared with most Western European countries, including France, Denmark, Austria and Ireland, the UK spends less on cancer per person, with Germany spending almost twice as much per head.

Why big pharma targets advanced cancers?

Most cancers are detected late when symptoms have manifested themselves, which renders treatment less effective and more costly. When cancer is caught early, as in some cases of breast and prostate cancer, tumours tend to be removed surgically or killed by chemoradiation therapy (CRT) and this, for many people, provides a “cure”, although in some cases the cancer returns.

Studies in developed economies suggest that treatment costs for early-diagnosed cancer patients are two to four times less expensive than treating those diagnosed with advanced-stage cancer. Notwithstanding, there are physical, psychological, socio-economic and technical challenges to accessing early cancer diagnosis and these conspire to delay cancer detection. Thus, big pharma companies have traditionally aimed their new cancer drugs at patients with advanced forms of the disease. This provides pharma companies access to patients who are willing to try unproven therapies, which significantly helps in their clinical studies. And further, big pharma is advantaged because regulators tend to support medicines that slow tumour growth and prolong life, albeit by a few months.

Imfinzi: the only immunotherapy to demonstrate survival at three years

A good example of this is AstraZeneca’s immunotherapy drug called Imfinzi (durvalumab) used in unresectable stage-III non-small cell lung cancer (NSCLC), which has not spread outside the chest and has responded to initial chemoradiation therapy. Imfinzi works by binding to and blocking a protein called PD-L1, which acts to disguise cancer cells from your immune system. Imfinzi removes the disguise so that your immune system is better able to find and attack your cancer cells.

Findings presented at the June 2019 meeting of the American Society of Clinical Oncology (ASCO), build on a clinical study of Imfinzi reported in the September 2018 edition of The New England Journal of Medicine, and suggest that Imfinzi is the only immunotherapy to demonstrate survival at three years in unresectable stage-III NSCLC. AstraZeneca has begun a phase-3 clinical study of the PD-L1 inhibitor protein in stage II NSCLC patients.

Some information about AstraZeneca

AstraZeneca is a British-Swedish multinational biopharmaceutical company with a market cap of US$107bn and annual revenues of US$22bn. The company operates in over 100 countries, employs more than 61,000, has its headquarters in Cambridge, UK, and is recovering after patents expired on some of its best-selling drugs and a failed takeover bid in 2014 by Pfizer.

You might also be interested in:

A paradigm shift in cancer diagnosis

Patents, legacy drugs and new biologics

When pharma companies develop a new drug, they can apply for a patent that stops other companies from making the same thing. A patent lasts for 20 years, after which point other producers can replicate the drug and its selling price plummets. This happened to AstraZeneca’s when the patents expired on two of its best-selling drugs: Crestor (rosuvastatin), and Nexium (esomeprazole). The former is a statin that slows the production of cholesterol by your body, lowers cholesterol and fats in your blood and is used to reduce your chances of heart disease and strokes. The latter is a drug used to treat symptoms of gastroesophageal reflux disease (GERD) and other conditions involving excessive stomach acid. Unlike some of its rivals, these were oral medicines based on small molecules that are easy for generic manufacturers to copy, which made AstraZeneca vulnerable to cut-price competition immediately after the legal protection of the drugs had expired. Notwithstanding, AstraZeneca’s new generation of biologic medicines, which it launched in the first decade of this century, are protected to some degree by the fact that they are difficult to copy as they are manufactured using cells, instead of big chemistry sets used to make conventional drugs.

AstraZeneca’s history with early stage cancer therapies

Baselga’s gamble benefits from the fact that AstraZeneca developed an interest in the detection of early stage cancer before his appointment. Today, AstraZeneca is active in clinical studies with other biopharma companies and leading academic institutions targeting earlier-stage therapies.

Working with collaborators over the past two decades, AstraZeneca has tested a number of drugs including Iressa (Gefitinib) and Tagrisso (Osimertinib) in cancers from stage-I onward, in some cases to try to shrink tumours before they are removed surgically. Tagrisso is a potential star-drug for AstraZeneca. It was originally developed to treat a group of lung cancer patients whose cancer had become resistant to established tyrosine kinase inhibitor therapies such as Iressa and Roche’s Tarceva (erlotinib). Tagrisso surprised AstraZeneca as it turned out to be better than Iressa and Tarceva when used in untreated patients with epithelial growth factor receptor (EGFR) mutations. EGFR is a protein present on the surface of both normal cells and cancer cells, and are most common in people with lung adenocarcinoma (a form of NSCLC), more common with lung-cancer in non-smokers, and are more common in women.

Epithelial growth factor receptor (EGFR)

Think of EGFR as a light switch. When growth factors (in this case tyrosine kinases) attach to EGFR on the outside of the cell, it results in a signal being sent to the nucleus of the cell telling it to grow and divide. In some cancer cells, this protein is overexpressed. The result is analogous to a light switch being left in the "on" position, telling a cell to continue to grow and divide even when it should otherwise stop. In this way, an EGFR mutation is sometimes referred to as an "activating mutation". Tagrisso "targets" this protein and blocks the signals that travel to the inside of the cell and growth of the cell stops. In 2003, when AstraZeneca received regulatory approval of Iressa we had little understanding about EGFR. Today however about 50% of drugs approved for the treatment of lung cancer address this particular molecular profile.

Technological challenges

Baselga’s gamble is assisted by advances in liquid biopsies, which work by detecting fragments of malignant tumour DNA in the bloodstream to identify oncogenic drivers, which help treatment selection. The challenge of this approach is that tumours shed meniscal amounts of circulating tumour DNA (ctDNA), which significantly raises the difficulty of detecting the genetic signals that oncologists need to identify specific cancers and select treatments. ctDNA should not be confused with circulating free DNA (cfDNA), which is a broader term that describes DNA that is freely circulating in the bloodstream but is not necessarily of tumour origin.

The good news for Baselga is that in recent years looking for ctDNA has become a viable proposition because of improvements in DNA sequencing technologies, (see below) which make it possible to scan fragments and find those few with alterations that may indicate cancer. While other blood-based biomarkers are being investigated, the advantage of ctDNA is that it has a direct link to a tumour and can be very specific at identifying cancer. ctDNA also provides a means to profile and monitor advanced stage cancers to inform treatments.

Notwithstanding, a paper published in the June 2018 edition of the Journal of Clinical Oncology suggests that, “there is insufficient evidence of clinical validity and utility for the majority of ctDNA assays in advanced cancer”, and therefore it is still early to adopt cfDNA analysis for routine clinical use.

Next generation genome sequencing

DNA sequencing is the process of determining the sequence of nucleotides in a section of DNA. The first commercialised method was “Sanger Sequencing”, which was developed in 1977 by Frederick Sanger, a British biochemist and double Nobel Laureate for Chemistry. Sanger sequencing was first commercialized by Applied Biosystems, and became the most widely used sequencing method for approximately 40 years. More recently, higher volume Sanger sequencing has been replaced by next-generation sequencing (NGS) methods, which cater for large-scale, automated genome analyses. NGS, also known as high-throughput sequencing, is a general term used to describe a number of different state-of-the-art sequencing technologies such as Illumina’s Solexa sequencing. These allow for sequencing of DNA and RNA significantly more quickly and cheaply than the previously used Sanger sequencing and has revolutionised the study of genomics and molecular biology.

Can AstraZeneca acquire success?

Baselgo’s gamble is not helped by the relative dearth of biotech companies engaged in clinical studies of early stage cancers. This significantly narrows AstraZeneca’s options if it wants to buy-in clinical-phase assets to fit with Baselga’s strategy.

Notwithstanding, there are at least two biotech companies of potential interest to AstraZeneca. One is Klus Pharma, founded in 2014, based in Monmouth Junction, New Jersey, US, and acquired for US$13m in October 2016 by the Sichuan Kelun Parmaceutical Co., a Chinese group based in Chengdu. Another is Dendreon, a biotech company based in Seal Beach, California, US. In 2014 Dendreon filed for chapter 11 bankruptcy. In 2015 its assets were acquired by Valeant Pharmaceuticals. In 2017, the Sanpower Group, a Chinese conglomerate, acquired Dendreon from Valeant for US$820m.

Klus is recruiting patients with stage-I rectal cancer for a phase 1/2 clinical study of its anti-HER2 antibody drug, and is also working to extend its flagship product, Provenge (sipuleucel-T) as an option for patients with low-risk prostate cancer. Provenge is an autologous cellular immunotherapy. It was the first FDA-approved immunotherapy made from a patient’s own immune cells. Since its approval in 2010, nearly 30,000 men with advanced prostate cancer have been prescribed the therapy.

Unicorns threaten AstraZeneca’s strategy for early cancer

Perhaps the biggest threat to Baselga’s gamble is competition from unicorns, which include Grail, and Guardant Health.

Grail
Grail was spun-out of the gene sequencing giant Illumina in 2016 and backed by more than US$1.5bn in funding, including money from Microsoft cofounder Bill Gates and Amazon founder Jeff Bezos. Grail is on a quest to detect multiple types of cancer before symptoms manifest themselves by way of a single, simple and cheap blood test to find fragments of ctDNA. Grail has made significant progress in its quest to develop highly sensitive blood tests for the early detection of many types of cancer, but it still has to engage in further large-scale clinical studies. At the 2018 ASCO conference, the company presented data from its Circulating Cell-free Genome Atlas (CCGA) project, which showed detection rates ranging from 59% to 92% in patients with adenocarcinoma, squamous cell and small cell lung cancers. The rate of false positives - a major concern for the oncology community - was under 2%.

In an effort to improve its technology and its outcomes, Grail has been working with researchers from the Memorial Sloan Kettering Cancer Center, MD Anderson Cancer Center and the Dana-Farber Cancer Institute, to develop a new assay. According to results published in the March 2019 edition of the journal Annals of Oncology, this joint venture has successfully come up with a method, which can detect mutations in NSCLC patients’ blood with high sensitivity. In some cases, the technology was useful when tissue biopsies were inadequate for analysis. The new tool uses Illumina’s “ultradeep next-generation sequencing", which involves reading a region of DNA 50,000 times, on average, to detect low-frequency variants. White blood cells were also sequenced to filter out "clonal hematopoiesis", which are noncancerous signals that can come from bone marrow. The sequencing information was then fed to a machine learning algorithm developed by Grail to determine mutation readouts.

Guardant Health
The other unicorn for AstraZeneca to watch is liquid biopsy developer Guardant Health. Founded in 2013, it is now an US$8bn precision oncology company based in Redwood City, California US. In April 2019 Guardant presented data of its oncology platform at the American Association of Cancer Research (AACR) in Atlanta, US. The platform leverages Guardant’scapabilities in technology, clinical development, regulatory and reimbursement to drive commercial adoption, improve patient clinical outcomes and lower healthcare costs. In pursuit of its goal to manage cancer across all stages of the disease, Guardant has launched two next-generation sequencing liquid biopsy-based Guardant360 and GuardantOMNI tests for advanced stage cancer patients, for minimal residual disease/recurrence monitoring and for early detection screening, respectively.

The Guardant360 test is used to track patients’ responses to drugs and select most effective future therapies. It can identify alterations in 73 genes from cfDNA and has been used by more than 6,000 oncologists, over 50 biopharmaceutical companies and all 28 of the National Comprehensive Cancer Network Centers.

Further, Guardant has launched a new liquid biopsy called Lunar. At the April 2019 AACR meeting the company presented data of Lunar’s use as a screen for early-stage colorectal cancer. The assay was used to test plasma samples taken from 105 patients with colorectal cancer and 124 age-matched cancer-free controls. It is the test’s utility as a screen for early-stage disease that should interest AstraZeneca most. Guardant expects to position Lunar as something approaching a true diagnostic: a screening test to identify solid tumours in the healthy population. Wider clinical studies of Lunar are expected to start soon and Guardant believes that Lunar’s market opportunity as a cancer screen is some US$18bn and sees a US$15bn market opportunity in recurrence monitoring.

Also, in April 2019 Guardant acquired Bellwether Bio, a privately held company founded in 2015, for an undisclosed sum. Bellwether is focused on improving oncology patient care through its pioneering research into the epigenomic content of cfDNA. This could aid Guardant in its efforts to develop a cancer screen and further advance its research into cancer detection at earlier stages of the disease.

Guardant is well positioned to develop individual early indications of cancer. Grail, on the other hand, is well positioned to develop a pan-cancer test. Notwithstanding, both companies need to engage in further lengthy, large-scale clinical studies before it will become clear which of these strategies will be more successful. However, both unicorns and other start-ups are potential competitors to AstraZeneca’s endeavours to target early cancer.

Takeaways

AstraZeneca’sproposed bold and risky shift in its R&D strategy is to be welcomed since the early detection and treatment of cancer should significantly enhance the chances of a cure, which would radically improve the quality of life for millions and substantially reduce the vast and escalating costs associated with the disease. AstraZeneca has some advantages since over the past two decade it has significantly enhanced its technology and been developing a platform of therapies for early stage cancer. Notwithstanding, for its strategy to target early stage cancer to be successful the company will have to overcome intense, fast growing, well-resourced competition and substantial technical and markets challenges.

expand

view in full page

9 years, 2 months ago

24328
0
Facebook

Twitter

Google+

LinkedIn

Report

Is immunotherapy a breakthrough in cancer treatment?

HealthPad

Directory:

Cancer

Tags:

preventative strategies

Immunotherapy drugs heralded as game changing cancer treatment
MD Anderson Professor Allison stripped cancer’s ability to evade attack
Nivolumab focuses on the environment around a cancer
Immunotherapy drugs are too expensive as sustainable treatments
The future is personalized medicine says cancer expert Karol Sikora

A new drug class that neither directly treats nor kills cancer is heralded as a game changer in cancer treatment.

New hope for late stage cancer patients

In March 2015, the American Food and Drug Administration (FDA) awarded an expanded approval for Opdivo (nivolumab), to treat non-small-cell lung cancer, which is the most common type of lung cancer, and means lung cancer patients who have failed other therapies and have no other treatment options, have another shot at containing their tumors. In June 2015, the European Commission approved the same Bristol-Myers Squibb drug in a fast track assessment for previously treated advanced melanoma patients.

Accelerated assessment was given in Europe because Opdivo (nivolumab) qualified as a “Medicinal product of major interest from the point of view of public health, and in particular from the viewpoint of therapeutic innovation.”

FDA and EU approvals of the drug Opdivo, opens the door for other, next-generation immunotherapies to treat advanced cancers. These are heralded as a new class of game changing drugs. But are they?

The genesis

Because cancer is a result of your body’s own cells growing abnormally, your immune system is held back from recognising cancer as foreign and potentially harmful. This is important because without such checks your immune system would kill you.

Professor James Allison, director of MD Anderson’s immunotherapy platform, which cultivates, supports and tests new developments of immunology-based drugs and combinations, is credited with ground-breaking research that stripped away cancer’s ability to evade attack by the immune system. Allison’s discoveries led to nivolumab to improve the survival rate of patients with metastatic melanoma, and his insights into the basic biology of immune system T cells is broadly applicable to a variety of cancers.

How it works

These new drugs release the body’s own weapons: killer white blood cells called T cells, and have been likened to taking the brakes off the immune system so that it is able to recognise tumors it wasn't previously recognising, and react to destroy them.

Unlike traditional cancer therapies such as surgery, chemotherapy, radiation or the anti-cancer drugs, immunotherapy does not target the tumor itself. Instead, it focuses on the environment around the cancer, and releases a check on the immune system’s appetite for anything that it does not recognize, so the body’s own defences can recognize tumor cells as targets. Allison says, “This drug doesn’t treat cancer; it doesn’t kill cancer cells so you can’t inject it and expect cancer to melt away immediately because it won’t.”

However, when nivolumab is combined with tumor-targeted treatments, it lowers the risk of recurrent cancers. It does this by training the body’s T cells to recognize specific features of tumors, just as they do for viruses and bacteria. Thus, the immune system itself is programmed to destroy any returning or remaining cancer.

Too costly

Although immunotherapies are generating excitement among cancer clinicians and researchers, clinical studies on melanoma patients show relatively modest prolongations of life, compared with historical norms, at significant costs. For example, the cost of Opdivo (nivolumab) for one patient is about £100,000 per year.

Speaking at the 2015 American Society of Clinical Oncology (ASCO) conference in Chicago, Dr Leonard Saltz from Memorial Sloan Kettering Cancer Center, New York City, suggested that new immunotherapies would cost more than US$1 million per patient per year at the higher dose currently being studied in many different cancer types, and warned, "This is unsustainable.... We must acknowledge that there must be some upper limit to how much we can, as a society, afford to pay to treat each patient with cancer . . As someone who worries about making cancer care available to everyone and minimizing disparities, I have a major problem with this: these drugs cost too much."

Takeaway

According to cancer expert Professor Karol Sikora the future of cancer treatment is personalized medicine rather than new immunotherapy products. Personalized cancer care takes into account the individual’s disease, and their personal circumstances. According to Sikora, “The extent to which treatment can be tailored to an individual has been limited by crude descriptions of their disease, and generic treatment options. Advances in genomics and drug responsiveness are leading to more detailed descriptions of a patient’s cancer and better-targeted treatments, which offer significant advantages over blunderbuss chemotherapies. Personalised medicine is the real future for all our patients. Forget the drug hype; this is where the real hope lies”.

Here Mike Birrer, Professor of Medicine at the Harvard University Medical School, and Director of the Cancer Center at Massachusetts General Hospital describes personalised medicine:

expand

view in full page

Tag

Sponsored

AstraZeneca’s strategy to target early cancer

Directory:

Tags:

Is immunotherapy a breakthrough in cancer treatment?

Directory:

Tags:

Immunotherapy drugs heralded as game changing cancer treatment

MD Anderson Professor Allison stripped cancer’s ability to evade attack

Nivolumab focuses on the environment around a cancer

Immunotherapy drugs are too expensive as sustainable treatments

The future is personalized medicine says cancer expert Karol Sikora

New hope for late stage cancer patients

The genesis

How it works

Too costly

Takeaway