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Thursday, October 06, 2016

Not So Wondrous Drugs? - New Warnings about Severe Adverse Effects of New, Heavily Marketed Drugs for Hepatits C,

Background - Wonder Drugs for Hepatitis C

In our April, 2014, post we noted how Sovaldi (sofosbuvir), the new antiviral drug made by Gilead for hepatitis C was touted as a "triumph of of medical technology."  In that, and subsequent posts we discussed how such claims were not buttressed by much good data from clinical research.

We could find only one published randomized clinical trial of sofosbuvir (and ribavirin), which compared it to the older drug used to treat hepatitis C, peg-interferon (and ribavirin).  At best, the new drug showed about the same ability to eliminate detectable virus from the patients' blood in the short-term as did the older drug.  The new drug also produced fewer unpleasant side effects, but possibly more severe adverse effects.  Just like all previous known published trials of hepatitis C treatments, this trial of sofosbuvir did not follow patients long enough to determine if the drug had any effect on the serious, but not inevitable long-term complications of hepatitis C infection, severe hepatitis, cirrhosis, liver failure, liver cancer, and premature death.

I could find no other published trials of sofosbuvir versus either older drugs or placebo.  Most of the subsequently published, and loudly hyped studies of the drug were of highly selected patients, and did not include control groups which did not receive sofosbuvir.  So the very high short term "cure" rates - which were really rates of elimination of detectable virus from the blood, could have been mainly a function of these studies' highly selected patient populations.

Yet the lack of strong evidence that sofosbuvir, and subsequent competing drugs actually made patients better, i.e., feel better, function better, avoid serious subsequent medical problems, or live longer, did not stop tremendous enthusiasm in the media for the new drug.  Much of it doubtless stemmed from huge marketing and public relations expenditures.  Nor did did the lack of evidence stop Gilead and other drug makers from pricing the new drugs in the stratosphere.  Initially a 12 week course of of Sovaldi cost $84,000.

Since then, there has been tremendous buzz about the price of these new antiviral drugs for hepatitis C, and tremendous anxiety about the consequent difficult access to these presumptively "life saving" therapies.  However, my and others' questions about whether these drugs actually benefit patients, and whether any benefits might be worth their harms, remained anechoic (See appendix below.)

The Harms of the "Wonder Drugs" Begin to Appear

Nowadays new drugs, devices, and other health care technologies are often touted based on little evidence.  What evidence is produced mainly comes from commercially sponsored clinical trials.  Commercial sponsors may manipulate the design, implementation, analysis and dissemination of these studies to increase the likelihood that they will make their products look good.

In particular, such trials may fail to detect adverse effects of the new products to be hyped.  The trials  often enroll only small numbers of patients, decreasing the likelihood of finding rare but serious problems.  Often patients who have any health problems other than the disease of interest are excluded from trials, decreasing the likelihood of detecting adverse events that might affect patients with multiple morbidities or on other treatments.  Trials may fail to follow patients long-term, so they may fail to detect adverse effects that appear only after prolonged therapy.  These sorts of problems certainly afflicted the very few real clinical trials of sofosbuvir, and other new antiviral drugs for hepatitis C.   

So it should not have been surprising that sofosbuvir has now been found to produce two kinds of severe adverse events that were undetected, or at least undisclosed when it was launched.  The second kind of adverse event was just announced, and also seems to occur after administration of other new anti-hepatitis C drugs.

Severe Heart Rhythm Abnormalities

In March, 2015, as discussed by Dr John Mandrola in Medscape,

As reported by heartwire , the US FDA recently announced a change in labeling for the hepatitis-C antivirals ledipasvir/sofosbuvir (Harvoni, Gilead Sciences) and sofosbuvir (Sovaldi, Gilead Sciences) after their manufacturers reported bradycardia, pacemaker intervention, and even death in patients who took the medications along with amiodarone. Notably, six of these nine cases occurred within 24 hours of sofosbuvir dosing.

While Dr Mandrola was concerned about this adverse effect, the news media put more emphasis on the Wall Street analysts who thought the problem would have "zero impact" on sales of the fabulously expensive antiviral drugs. (See this post by Ed Silverman on PharmaLot.)

So all remained serene, until this week.

Reactivation of Hepatitis B Infection

On October 4, 2016, Medscape reported

Patients with a past or current hepatitis B virus (HBV) infection can experience sometimes fatal HBV reactivation if they take any of nine direct-acting antivirals for hepatitis virus C (HCV) infection, the US Food and Drug Administration (FDA) announced today.

The agency will require a boxed warning for the drugs advising clinicians to screen patients for evidence of a past or current HBV infection before ordering antiviral treatment for HCV.

Also,

The FDA said in a news release that it had identified 24 cases of HBV reactivation in coinfected patients treated with these antivirals from November 22, 2013, to July 18, 2016, in reports to the agency and published literature. Two patients died, and one needed a liver transplant.

Why were we not made aware of this before?  Failure to detect this adverse effect was apparently due to the exclusion of patients with a history of hepatitis B from previous studies of the new drugs.  As we mentioned above, commercially sponsored trials often exclude patients with nearly any medical conditions other than the one of interest.  Yet hepatitis C patients often have comorbidities.  I

clinical trials for the HCV drugs in question did not report HBV reactivation because they excluded patients infected with HBV.

Will this prompt a reexamination of our enthusiasm for new antiviral hepatitis C treatments? I suspect not. Even FDA officials suggested we should not be too alarmed. In particular, Dr. John Farley, deputy director of FDA's Office of Antimicrobial Products, said according to NBC News,

I think it is important to recognize that these hepatitis C drugs are lifesaving medications. What we don't want to do is discourage patients with hepatitis C from getting treatment,...


But remember, there has never been a controlled trial that showed that treatment of hepatitis C with anything actually reduced the risk of later severe hepatitis, cirrhosis, liver failure, liver cancer, or premature death. And there may be other adverse effects of this new treatment that remain unknown.

Even government regulators, who are supposed to put the public health ahead of the profits of the pharmaceutical industry, seem to have fallen for the life saving miracle drug meme in this case.

Summary

The ongoing story of hepatitis C treatment demonstrates how hype and buzz, largely generated by marketing and public relations, and likely fueled by financial relationships among commercial health care firms and health care professionals and academics, has triumphed over rigorous skeptical evaluation of the best available evidence from clinical research.

There has never been good evidence that hepatits C treatments prolong life, or prevent severe liver disease in the long run.  There has never been good evidence that these drugs' clinical benefits outweigh their harms.  Yet they have been relentlessly promoted as game changers, miraculous, triumphant lifesaving medicines.

One obvious lesson is that health care professionals, policy makers, and the public at large have to be much more skeptical about commercial claims for drugs, devices, tests, etc.  We need to figure out when claims are coming from marketing departments and public relations hacks.  We need to figure out when researchers and professionals who are supporting these claims could be influenced by financial relationships with the firms benefiting from the claims.

Furthermore, it is high time to revisit all the regulatory and policy changes over the last 30 years that have put manufacturers in charge of the research meant to test their own health care products.

In conclusion, evidence-based medicine rigorously applied suggests that individual health care and health policy decisions should be driven by the best available evidence, mostly from clinical research, about the benefits and harms of tests, treatments, programs, and so on, in the context of what outcomes matter to patients.  The skepticism EBM should engender could lead to health care that is more about patients and their outcomes, and less about ideology, hype, and hucksterism. If only such skepticism were easier to find.


.......
APPENDIX - Clinical Research about Hepatitis C Treatments

Starting in March, 2014, we have posted about the lack of good evidence from clinical research suggesting these drugs are in fact so wondrous.  The drugs are now touted as "cures," at least by the drug companies, (look here), and physicians are urged to do widespread screening to find patients with asymptomatic hepatitis C so they can benefit from early, albeit expensive treatment.

However, as we pointed out (e.g., here and here)
-  The best evidence available suggests that most patients with hepatitis C will not go on to have severe complications of the disease (cirrhosis, liver failure, liver cancer), and hence could not benefit much from treatment.
-  There is no evidence from randomized controlled trials that treatment prevents most of these severe complications
-  There is no clear evidence that "sustained virologic response," (SVR), the surrogate outcome measure promoted by the pharmaceutical industry, means cure. 
-  While the new drugs are advertised as having fewer adverse effects than older drugs, it is not clear that their benefits, whatever they may be, outweigh their harms.

Furthermore, health care professionals and researchers with heftier credentials in clinical epidemiology and evidence based medicine than mine have since published similar concerns.  These included
- a report from the German Institute for Quality and Efficiency in Health Care (the English summary is here)
- an article in JAMA Internal Medicine from the Institute for Clinical and Economic Review (1)
- a report from the Center for Evidence-Based Policy (link here)
- an article in Prescrire International (2)

These publications and your humble scribe noted that the clinical trials or other types of clinical research about new hepatitis C treatment published in the most prominent journals had numerous methodologic problems that all seemed likely to make the new drugs look better, perhaps intentionally.  (See posts herehere, and here.)

References

 1. Ollendorf DA, Tice JA et al. The comparative clinical effectiveness and value of simeprevir and sofosbuvir in chronic hepatitis C viral infection. JAMA Intern Med 2014;174(7):1170-1171. Link here.
2. Sofosbuvir (Sovaldi), active against hepatitis C virus, but evaluation is incomplete. Prescrire Int 2015; 24: 5- 10. Link here.

ADDENDUM (11 October, 2016) - This post was republished on the Naked Capitalism blog

2 comments:

  1. A quick check on ClinicalTrials.gov did not turn up any Phase 4 studies examining longer term outcomes like prevention of cirrhosis or liver failure or liver cancer. What gives?

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  2. Also, there is a possibility that these new drugs may increase probability of liver cancer, at least for patients with cirrhosis. Some controversial new studies show unexpectedly high percent of liver cancer after HCV DAA treatment with cirrhosis:
    http://www.journal-of-hepatology.eu/article/S0168-8278(16)30271-9/fulltext
    http://www.journal-of-hepatology.eu/article/S0168-8278(16)30397-X/fulltext

    Some other studies do not show such increased probability of liver cancer occurence, and situation with cancer risks seems not clear at this moment.

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