Tuesday, November 22, 2011

Lessons from Xigris

I have been wanting to write for a while about the demise of Xigris, but work and other commitments have stalled my progress. But it is time.

Here is my disclosure: I have received research funding from BioCritica, a daughter company of Eli Lilly, the manufacturer of Xigris. I also happen to know well and hold in high esteem the depth of knowledge and integrity of several colleagues who worked on Xigris internally at Lilly.

But on to the story. Xigris has had a short and bumpy life. When the PROWESS study, the Phase III Xigris trial, was first published in the NEJM in 2001 [1], it was the first therapy to succeed in sepsis, reducing mortality by 6% from about 31% to about 25%, yielding the number needed to treat of 16. This was huge, as so many trials to date had failed, and no progress had been made in sepsis management for years. These data opened the door to the FDA approval, despite a hung advisory committee, where equal numbers of members voted for and against approval. The controversy centered on concerns for bleeding complications, as well as some protocol changes during the trial and a switch in the manufacturing process. The latter concern was allayed by the Agency's detailed analysis and the finding of equivalence. There was a signal in a subgroup analysis that the drug might have been most effective among the most ill patients with a high probability of death, but not in their less ill counterparts. And despite the fact that the pivotal trial was not specifically performed in these patients, the approval for use specified just such a population.

So, despite the controversy, the drug was approved, though several post-marketing commitment studies were mandated. ENHANCE [2, 3] was an international study whose findings broadly confirmed the safety and efficacy of the drug, while the ADDRESS study [4], done in patients at low risk for death, was terminated early for lack of efficacy.

It seemed that PROWESS ushered in an era of positive results in sepsis. Shortly after its publication, other studies on the use of early goal-directed therapy [5], low-dose steroids [6] and tight glucose control [7] appeared in high impact journals, and the years of failure in sepsis management seemed to be over.  

In the meantime, and amid further controversy [8], Lilly supported the creation of the Values, Ethics and Rationing in Critical Care (VERICC) Task Force [9, 10], in addition to giving funding for the international Surviving Sepsis Campaign (SSC), which has resulted in the evidence-based practice guideline for sepsis management [11, 12] and an implementation program for the sepsis bundles, jointly sponsored by the SSC and the Institute for Healthcare Improvement [13]. The latter 2-year program enrolled over 15,000 patients world-wide, and achieved a doubling of bundle compliance from 18% to 36% with a concurrent drop in adjusted mortality of 5%. Because of several methodological issues and the lack of transparency about what it took to implement the bundle, it has never been clear to me a). whether there was causality between the bundle and mortality, and b). whether this effort was cost-effective.

But that aside, Xigris continued to stir up controversy, and there were still safety concerns. Some very well done observational studies, however, continued to confirm its effectiveness and safety in the real world setting [14]. Yet the final trial, PROWESS-SHOCK (done because of fears of an increase in bleeding complications), where patients in septic shock received Xigris as a part of their early management, brought doom. It was this study, whose preliminary results appeared in the press release from October 25, 2011, that prompted Lilly to pull the drug off the world market, since no difference in the 28-day mortality was detected between placebo and Xigris arms. Ironically, the preliminary reports indicate that no excess bleeding was noted in the treatment arm.

So, after roughly 10 years and millions of dollars, Xigris disappeared. But what can we learn from its story? There are many lessons that we should carry away, some about the way we do research, some about marketing practices, but all of them are about the need for a higher level of conversation and partnership. The biggest elephant in this room is whether a manufacturer should be allowed to fund guideline development. It is a complicated issue, particularly given our native proneness to cognitive bias, but in my opinion yes. This certainly cannot be done in a quid pro quo way. Perhaps this is naïve but should it not simply be a question of good data? And why wouldn't a manufacturer give money for the development of sensible guidelines without strings attached when the data are good?

Unfortunately, to me, Xigris is the poster child for how broken our research enterprise is, as I have discussed in this JAMA commentary [15]. Until all stake holders start talking to each other and arriving at common, useful and achievable goals, this is a story that will repeat itself again and again. The fact that regulatory trials, with all of their expensive and flashy internal validity, concern themselves only with statistical issues and care nothing about what happens in the real world is a travesty on many levels. The fact that it costs nearly $1 billion to bring a drug to market means that only big Pharma can bankroll such a gamble, and in return must demand big profits. The fact that this $1 billion fails to bring us studies that help clinicians and policy makers understand fully how to optimize the use of a drug once it is on the market is inexcusable. What we need is more intellectually honest discussions leading to novel pragmatic ways to answer the relevant questions in a timely manner and without bankrupting the system.

So, does the obvious financial interest mean that manufacturers should stay out of these discussions? I happen to think that they need a prominent place at the table. I actually think that the current fiasco is largely the result of too little interaction and too little cross-pollination of ideas: when we all sit around the table a nod in agreement, there is little progress. Deeper and novel understanding is built on disagreement and debate. Therefore, to leave the manufacturers out would invite further irrelevance. The bottom line is that we are all conflicted, and, according to the editors of PLoS, non-financial conflicts of interest, though more subtle and difficult to discern, may present an even bigger threat to much of what we do [16]. Elbowing out a party with an obvious conflict may have the unintended consequence of leaving some of the more insidiously conflicted others to run the show. And although we can argue whether profit is the healthiest driver for performance in healthcare, the reality is that our entire healthcare "system" is built around profit-making. Therefore it is disingenuous to single out one player over others.

On the positive side, the halo effect around Xigris brought a ton of attention to sepsis and its management. As Wes Ely conjectured in this piece, our improved understanding of sepsis (largely due to all the attention Xigris brought to it, in my opinion), is probably what rendered the drug useless in PROWESS-SHOCK. So, after all the hype, the noise and the hoopla, what is left is a company less one drug and hundreds of millions of dollars, and a disease area with a whole lot of what amounted to public health investment, with a vastly improved understanding of the disease state. How much is this benefit worth?


[1] Bernard GR, Vincent JL, Laterre PF, et al: Efficacy and safety of recombinant human activated protein C for severe sepsis. N Engl J Med 2001; 344:699–709
[2] Bernard GR, Margolis BD, Shanies HM, et al. Extended Evaluation of Recombinant Human Activated Protein C United States Trial (ENHANCE US). A Single-Arm, Phase 3B, Multicenter Study of Drotrecogin Alfa (Activated) in Severe Sepsis. Chest 2004;125:2206-16
[3] Vincent JL, Bernard GR, Beale R et al.
Drotrecogin alfa (activated) treatment in severe sepsis from the global open-label trial ENHANCE: further evidence for survival and safety and implications for early treatment. Crit Care Med 2005;33: 2266-77
[4] Abraham E, Laterre P-F, Garg R, et al. Drotrecogin Alfa (Activated) for Adults with Severe Sepsis and a Low Risk of Death. New Engl J Med 2005;353:1332-1341
[5] Rivers E, Nguyen B, Havstad S, et al. Early goal-directed therapy in the treatment of severe sepsis and septic shock. N Engl J Med 2001;345:1368-1377
[6] Annane D, Seville B, Charpentier C, et al. Effect of treatment with low doses of hydrocortisone and fludrocortisone on mortality in patients with septic shock. JAMA 2002;288:862-871
[7] van den Berghe G, Wouters P, Weekers F, et al. Intensive insulin therapy in the critically ill patients.  N Engl J Med 2001;345:1359-1367 
      [8] Eichacker PQ, Natanson C, Danner RL. Surviving Sepsis – Practice Guidelines, Marketing Campaigns and Eli Lilly. N Engl J Med 2006;355:1640-2 
      [9] Sinuff T, Kahnamui K, Cook DJ, et al. Rationing critical care beds: A systematic review. Crit Care Med 2004;32:1588-97
      [10] Truog RD, Brock DW, Cook DJ, et al. Rationing in the intensive care unit. Crit Care Med 2006;34:958-63
      [11] Dellinger RP, Carlet JM, Masur H, et al: Surviving Sepsis Campaign guidelines for management of severe sepsis and septic shock. 2004;32:858-73 
      [12] Dellinger RP, Levy MM, Carlet JM, et al: Surviving Sepsis Campaign: International guidelines for management of severe sepsis and septic shock: 2008. Crit Care Med 2008;36:296-327. Erratum in Crit Care Med 2008;36:1394-96
      [13] Levy MM, Dellinger RP, Townsend SR, et al. The Surviving Sepsis Campaign: Results of an international guideline-based performance improvement program targeting severe sepsis. Crit Care Med 2010;38:367-74
      [14] Lindenauer PK, Rothberg MB, Nathanson BH, et al. Activated protein C and hospital mortality in septic shock: A propensity-matched analysis. Crit Care Med 2010;38:1101-7
      [15] Zilberberg MD. The clinical research enterprise: Time for a course change? JAMA 2011;305:604-5 
      [16] The PLoS Medicine Editors (2008) Making Sense of Non-Financial Competing Interests. PLoS Med 5(9): e199. doi:10.1371/journal.pmed.0050199


  1. 28 day mortality is a silly outcome in critical care. I'll be interested to hear your thoughts when the 90-day end points are released for PROWESS-SHOCK and indeed show benefit.

  2. Dear Anonymous, the 28-day mortality is somewhat arbitrary and may or may not correlate with longer-term outcomes, I agree. I do think it all goes to my assertion that there is a persistent disconnect between what the FDA requires and the needs of clinicians and policy makers. This needs to be fixed, or at least the gap needs to narrow.

    I am very much looking forward to the full publication of PROWESS-SHOCK!