Bevacizumab In Colon Cancer – “A Shot Across The Bowel”

Colon2 130320.01 lo resAn E-Publication article in the February Journal of Clinical Oncology analyzes the cost efficacy of Bevacizumab for colon cancer. Bevacizumab, sold commercially as Avastin, has become a standard in the treatment of patients with advanced colorectal cancer. Indeed, Bevacizumab plus FOLFOX or FOLFIRI, are supported by NCCN guidelines and patients who receive one of these regimens are usually switched to the other at progression.

A Markov computer model explored the cost and efficacy of Bevacizumab in the first and second line setting using a well-established metric known as a Quality-Adjusted Life Year (QALY). In today’s dollars $100,000 per QALY is considered a threshold for utility of any treatment. To put this bluntly, the medical system values a year of yavastinour life at $100,000. The authors confirmed that Bevacizumab prolongs survival but that it does so at significantly increased costs. By their most optimistic projections, Bevacizumab + FOLFOX come in at more than $200,000 per QALY. Similar results were reported for Canadian, British and Japanese costs. Though more favorable, the results with FOLFIRI + Bevacizumab still came in above the $100,000 threshold.

No one doubts that Bevacizumab provides improved outcomes. It’s the incremental costs that remain an issue. Society is now confronting an era where the majority of new cancer agents come in at a cost in excess of $10,000 per month. Where and how will we draw the line that designates some treatments unaffordable? On the one hand, clinical therapies could be made available only to the “highest bidder.” However, this is contrary to the western societal ethic that holds that medical care should be available to all regardless of ability to pay. Alternatively, increasingly narrow definitions could be applied to new drugs making these treatments available to a shrinking minority of those who might actually benefit; a form of “evidence-based” rationing. A much more appealing option would be to apply validated drug predication assays for the intelligent selection of treatment candidates.
Avastin-MOA-Overview
In support of the latter, the authors state, “Bevacizumab potentially could be improved with the use of an effective biomarker to select patients most likely to benefit.” This is something that genomic (DNA) profiling has long sought to achieve but, so far, has been unable to do. This conceptual approach however is demonstrably more attractive in that all patients have equal access, futile care is avoided and the costs saved would immediately provide highly favorable QALY’s as the percentage of responders improved.

Similar to the recent reports from the National Health Service of England, the American public now confronts the challenge of meeting the needs of a growing population of cancer patients at ever-higher costs. It is only a matter of time before these same metrics described for colon cancer are applied to lung, ovarian and other cancers for which Avastin is currently approved.

At what point will the American medical system recognize the need for validated predictive platforms, like EVA-PCD analyses, that have the proven capacity to save both money and lives? We can only wonder.

Rationed or Rational: The Future of Cancer Medicine

Disturbing news from Britain’s Health Service on Monday, January 12, described the National Health Services’ decision to “delist” 25 of the nation’s 84 currently available chemotherapy drugs from their formulary. Citing the rising cost of cancer therapy Professor Peter Clark, chair of the Cancer Drug Fund said that the CDF, originally established in 2011, had already exceeded its annual budget. From ₤280 million in 2014 the costs for 2015 are projected to rise to ₤340 million. In defense of the policy Dr. Clark said the delisted drugs “did not offer sufficient clinical benefit.”

avastinAn examination of the delisted drug should raise concern for medical oncologists. Among those delisted are Bevacizumab (Avastin) for colorectal cancer, Eribulin (Haloven) and Lapatinib (Tykerb) for breast cancer and Pemetrexed (Alimta) for advanced lung cancer. Additionalhalaven deletions include Bendamustine (Treanda) for some non-Hodgkin’s lymphoma, Bortezomib (Velcade) for relapsed mantle cell lymphoma and Waldenström’s macroglobulinemia. Bortezomib will also be limitedvelcade_MP_thumb in some cases of myeloma, while Cetuximab will be unavailable as second or third line treatment in colorectal cancer. For American oncologists these agents have become standards of care.

Many physicians in England are outraged. Mark Flannagan, executive chief of the Beating Bowel Cancer Fund described this as “bad news for bowel cancer patients” suggesting that 65% of patients with advanced colorectal cancers will confront the risk of an earlier death. Despite these draconian measures physicians may still have the opportunity to request delisted drugs under what is described as “exceptional cases.”

The breadth and scope of the drug restrictions are surprising. After all, Pemetrexed is one of the most widely used treatments for advanced lung cancer, Bevacizumab has become an established part of colorectal cancer management and Eribulin is a favored salvage regimen in recurrent breast. The withdrawal of Bortezomib, an active agent in mantle cell, Waldenström’s and myeloma, will not be suffered lightly by patients in need.

Are the problems confronting the UK an early harbinger of the same for the American medical system?

With aging populations in western societies and increasingly sophisticated medical technologies, the cost of medical care, particularly cancer care may soon become unmanageable. UK’s centralized medical care delivery through the National Health Service, a single payer system, was designed to save money. Despite its high-minded intentions, the NHS appears to be failing. While spending more money each year the dissatisfaction with medical delivery only grows. A nearly 12% increase in health care per person expenditures in England between 2009 and 2013 (₤1712 to ₤1912) was met with an 18% increase in patient complaints.

Among the problems are progressive layers of middle management that add cost without providing care.  Physicians find it more difficult to do their jobs while people inexpert in the delivery of medical care have been given decision-making power. As the English population has come to look upon health care as a right, some overuse medical services, even ER’s, for non-serious conditions. Reformers have suggested the solution may lie in charging fees for appointments or requiring an annual membership fee. In today’s political milieu however, few elected officials are likely to relish policies that end “free health care” in England.

What might solve this dilemma for medical oncology? An obvious solution is to apply resources where they are most likely to benefit patients, e.g. personalized care. While this seemed a pipe dream 20 years ago when we first introduced the concept, a growing chorus of scientists now embraces the idea. With their focus almost exclusively on genomics this new cadre of clinical investigators describe a future where each patient gets exactly the right treatment.

We applaud this thinking and fully agree. However, we must be prepared to use all platforms to achieve this worthy goal. To fill the current void phenotypic analyses offer substantive benefits. By capturing cancer biology at a functional level, these studies identify true “driver mutations,” and have the capacity to examine synergy and sequence-dependence, both beyond the scope of genomic analyses.

As human tumor primary culture analyses (such as EVA-PCD) have already been shown to double objective response rates and improve one-year survival, it is time for government officials and policymakers to re-examine the benefits of drug selection technologies that are available today.

Will the future of cancer medicine in the UK and the US be rationed under the duress of rising costs, or rational, through the application of available technologies capable of making intelligent cost- and life-saving decisions? That remains to be seen.

Breast Cancer and Avastin, the Ongoing Saga

As many are now aware, in November of 2011, the United States FDA withdrew approval for bevacizumab (Avastin) for the treatment of breast cancer. Medicare and the National Comprehensive Cancer Network  (NCCN) are now re-examining their guidelines. In the interim, reimbursement for Avastin is a patchwork of approvals and denials across the country.

Into this mix comes an interesting concept apparently floated by Roche’s European affiliates. Described in a brief press release was the suggestion that Roche might be prepared to attach Avastin reimbursement to its efficacy. That is – Roche would only demand payment from patients and third party payers if the treated patient revealed objective evidence of response. This is an interesting idea!

The concept of conditional reimbursement is extremely intriguing. Contrary to contemporary reimbursement policy, the purveyors of therapy would only receive compensation if they could prove benefit, not mind you, benefit in the broad brush Phase III tiny statistically significant result (e.g. the FDA approval of erlotinib plus gemcitabine in pancreatic cancer for a median survival advantage of 10.6 days!), but instead very real benefit on a patient-by-patient basis.

We use erlotinib plus gemcitabine, as well as Avastin combinations, to great benefit for many of our patients and applaud the availability of these drugs and combinations. But we never, just give them. Were the federal government, major payers or HMOs to be prepared to reimburse novel therapies predicated on their efficacy, we might envisage a meaningful advance in cancer therapeutics.

Today, few small laboratories, start-up companies and early stage biotech firms have the resources to marshal multi-million dollar clinical trials to test new therapies. This may in part be why advances in cancer therapy are moving so slowly forward.  The barriers to entry are insurmountable, causing many good ideas to fall by the wayside for lack of the hundreds of millions of dollars required to achieve FDA approval and Medicare reimbursement. But what if on an individual basis, reimbursement policies reflected the most meaningful of all endpoints – individual patient response and survival. Even the largest pharmaceutical companies are now coming to realize that despite their clout they too are suffering under the guidelines forced upon drug developers in this era of ever increasing regulation.

This is a concept worth pursuing. Let’s see where it goes.

English Patients Denied Access to Ipilimumab

Among the more interesting discoveries in recent years have been two breakthroughs in the management of malignant melanoma. One drug, vemurafenib, a tyrosine kinase inhibitor, acts specifically in patients who carry the BRAF (V600E) mutation. The second drug ipilimumab, offered commercially from Bristol-Meyers Squibb as Yervoy, is a monoclonal antibody that acts by blocking CTLA-4, thereby enhancing T-cell response to tumor antigens. While vemurafenib has a somewhat narrow target population, ipilimumab targets may extend to a broader range of melanoma patients and will likely find a role in other cancers.

The data supporting ipilimumab’s use in advanced melanoma was reported in a 2010 Phase III trial, which provided a superior median survival for those treated with the drug over those who received a placebo. Superior one and two-year survivals were also reported. Unfortunately, this did not rise to the level that met the standards of the English watchdog organization, National Institute for Health and Clinical Excellence (NICE). The chief executive of NICE did admit that the drug could “potentially be very effective for a small percentage of patients.” Unfortunately, under current NICE guidelines, that small percentage of patients will not have access to the drug.

This is not the first time that a drug, found effective for the treatment of a subpopulation of patients has been denied approval based upon cost efficacy and the comparatively limited population of patients who stand to gain.

The role of Avastin in breast cancer represents a similar dilemma for those patients who might benefit but cannot afford the out-of-pocket expenses. Indeed, NICE originally denied approval to bortezomib, a highly active drug for the treatment of multiple myeloma, based upon similar cost considerations.

What ipilimumab, Avastin and bortezomib have in common is that they are harbingers of the coming conflict between patients-in-need and society’s capacity to cover the increasing costs of cancer therapy. Cost efficacy questions will only be resolved when we have the capacity to identify likely responders prior to therapy, enabling us to use drugs only in those patients with the highest expectations of response. Marginal overall benefits that come at high price will continue to fail until we redouble our efforts to refine the process of drug selection for individual patients. Janet Woodcock, MD, from the FDA once said, that we need “a critical path” from bench to bedside to guide clinical decisions. The human tumor primary culture functional analyses that we employ can provide that critical path and we would hope limit the need for the broad-brush policy decisions that are being handed down by NICE and similar entities both here in the U.S. and abroad.

The Avastin Saga Continues

We previously wrote about bevacizumab (Avastin) and its approval for breast cancer. The early clinical trials revealed evidence of improved time to disease progression. This surrogate measure for survival benefit had, over recent years, gained popularity, as time to disease progression is a measure of the impact of a given treatment upon the patient’s response durability. It was hoped and believed that time to progression would be an early measure of survival.

Unfortunately, the survival advantage for the Avastin-based therapies in breast cancer has not met statistical significance. As such, careful review by the oncology drug committee of the FDA lead to a unanimous decision to remove Avastin’s indication in breast cancer. Avastin has not been removed from the market, but instead, cannot be promoted or advertised, nor do insurers necessarily reimburse it. This decision, however, will have a very big impact on Medicare patients and many others who are in managed care programs (HMOs).

There are no villains here. Instead, dedicated physicians empowered to scrutinize the best data could not prove beyond any doubt that the drug improved survival. The time to progression data was favorable and the survival data also trended in a favorable direction. But, the final arbiter of clinical approval — statistically significant survival — was not met.

The physicians who want to provide this for the patients, the company that produces the drug and the patients who believe it offers benefit all have legitimate positions. As Jerome Groopman, MD, once said, in a similar situation with regard to the FDA approval of interleukin 2 (a biological agent with profound activity in a small minority of melanoma and renal cell cancer patients), “I am confronted with a dilemma of biblical proportions, how to help the few at the expense of the many.”

The Avastin saga is but one example of what will occur repeatedly. The one-size-fits-all paradigm is crumbling as individual patients with unique biological features confront the results of the blunt instrument of randomized clinical trials. Our laboratory has been deeply involved in these stories for 20 years. When we first observed synergy for purine analogs (2CDA and fludarabine) with cytoxan, and then recommended and used this doublet in advanced hematologic malignancies (highly successfully, we might add) we were a lone voice in the woods. Eventually, clinical trials conducted at M.D. Anderson and other centers confirmed the activity establishing these treatments as the standards of care for CLL and low-grade lymphoma.

The exact same experience occurred in our solid tumor work when we combined cisplatin plus gemcitabine in pancreatic, ovarian, breast, bladder, lung and other cancers. While our first patient (presumably the first patient in the world) received cisplatin plus gemcitabine for drug-resistant recurrent ovarian cancer in 1995 — providing her an additional five years of life — it wasn’t until 2006 that the FDA approved the closely related carboplatin plus gemcitabine for this indication.

We now confront an even greater hurdle. With our discoveries, using novel combinations of targeted agents, we are years (perhaps decades) ahead of the clinical trial process. We know that patients evaluated in our laboratory with favorable profiles can respond to some of the newest drugs, many of which have already completed Phase I of clinical trials. It is our fervent belief that we could accelerate the drug development process if we could join with the pharmaceutical companies and the FDA to put these hypotheses to a formal test.

Again, there are no villains here. Patients want, and should, receive active drugs. Doctors should be allowed to give them. The drug companies want to sell their agents and the FDA wants to see good therapies go forward.

The rancor that surrounds these emotionally charged issues will best be resolved when we introduce techniques that match patients to active therapies. We believe that the primary culture platform used in our laboratory, and a small number of dedicated investigators like us, may be the answer to this dilemma.

We will redouble our efforts to apply these methods for our patients and encourage our patients to lobby their health care insurers and representatives to sponsor these approaches. To date, we have been unsuccessful in convincing any cooperative group to test the predictive ability of these selection methodologies. In response, I reiterate that I will gladly participate and, to the best of my ability, support at least the laboratory component of any fair test of our primary culture methodologies.

We stand at the ready for the challenge.

Not Responding to the Standard Cancer Treatment? Maybe You’re an Outlier

In a recent reply to a blog comment, I mentioned the term “outlier” to describe a woman with breast cancer who had an excellent response to bevacizumab-based therapy. This was part of a discussion about the drug and its role in cancer treatment. The term outlier was utilized to describe this woman’s excellent response to a drug combination that has not achieved statistically significant survival advantage in the general population of breast cancer patients.

While outliers may connote strangeness or removal from the norm, in contemporary cancer therapies being removed from the norm can be a very, very good thing. After all, a minority of cancer patients benefit durably from chemotherapy. Those patients fortunate enough to have long-term responses are the happy outliers who populate the scientific community’s grab bag of anecdotes.

However, to the individual patient, a good response is much more than an anecdote, it is a life saving experience, an experience that every cancer patient richly deserves. While clinical trials are designed to identify average improvements for average patients, virtually every trial conducted has patients who live much longer than average. They constitute the tail on the survival curve and almost every trial has several.

Our job should be to identify those true responders and treat them appropriately rather than denying them active treatments based on the failure of the average patient paradigm. In statistics, the term applied for these failures are “beta errors,” meaning that the investigators missed the benefit of a given treatment. By identifying active treatments in small subsets of patients, functional analytic tools (like the Rational Therapeutics EVA-PCD platform) enable us to select those small subsets for treatment regardless of average expectations.

A Tale of Two Lung Cancers

I was recently asked to speak at a community outreach mixer to describe our work in lung cancer. I invited two patients to join me:

  1. A woman in her early 50s who presented to medical attention with metastatic adenocarcinoma of the lung with brain involvement.
  2. A woman in her early 60s, also with metastatic adenocarcinoma with brain involvement.

Under the microscope their tumors appeared almost identical. But, in the laboratory, the profiles were distinctly different. Patient no. 1 revealed a highly sensitive profile to the EGFR-TKI erlotinib (Tarceva) that was demonstrably enhanced by VEGF inhibition (e.g. Bevacizumab, Avastin). The second patient was resistant to erlotinib and VEGF inhibition, but was highly sensitive to the doublet of platinum plus gemcitabine.

Both patients attended the mixer and spoke to the crowd. They both looked the picture of health, sporting their own hair with no significant toxicities from therapy. Both had completed Cyberknife brain radiation and had gone on to exactly the right treatment for them. Despite their similarities in presentation and histology, their treatments were extremely different. Yet, both have had excellent and durable responses.

Every lung cancer patient has the capacity to do well. It is our job to find out which drugs and combinations are most likely to achieve that end. Functional profiling provided both of these patients exactly the right treatment for them. With the Rational Therapeutics EVA-PCD platform, every patient is treated as an individual.

What’s Wrong with Avastin?

Nothing really. It’s a wonderful drug that incorporates the brilliant insights originally articulated by Judah Folkman, MD, at Harvard University. Dr. Folkman reasoned that:

  1. Cancers require oxygen and nutrients
  2. These would need to be delivered by a blood supply
  3. Tumors would avidly seek their own blood supply via humoral factors.

His groundbreaking work ultimately lead to the discovery of VEGF, as well as the FDA approval of Avastin, the monoclonal antibody that binds and inactivates circulating VEGF in patients. The problem isn’t with Avastin, it’s with the practice of oncology – the clinical trial process and the muddied waters that surround clinical utility of any drug, new or old.

There are no perfect drugs. There are simply drugs that work for certain patients. VEGF down-regulation is an attractive and highly appropriate therapy for a subset of cancer patients with many different diagnoses whose tumors use the VEGF pathway to their advantage. Avastin combined with carboplatin and taxol has improved the survival of lung cancer patients. Avastin plus folfox has improved survival for colon cancer patients. Avastin plus chemotherapy improves the survival of some breast cancer patients. The problem is that it doesn’t improve the survival of all breast cancer patients.

When the FDA rules on the clinical utility of a drug, they use a broad-brush approach that looks at the global outcomes of all patients, determining whether these glacial trends reflect a true climate change. The problem is that while Bethesda, Maryland may not be noticing significant changes in ocean levels, people who live on the Maldives are having a very different experience. As these scientists ponder the significance of Avastin, some breast cancer patients are missing out on a treatment that could quite possibly save their lives.

One breast cancer patient’s life saving therapy is another’s pulmonary embolism without clinical benefit. Until such time as cancer patients are selected for therapies predicated upon their own unique biology, we will confront one Avastin after another. Our solution to this problem has been to investigate the VEGF targeting agents in each individual patient’s tissue culture, alone and in combination with other drugs, to gauge the likelihood that vascular targeting will favorably influence each patient’s outcome. Our results to date in patients with non-small cell lung cancer, colorectal cancer and even rare tumors (like medullary carcinoma of the thyroid) suggest this to be a highly productive direction for future development.