Musings of a Dinosaur

A Family Doctor in solo private practice; I may be going the way of the dinosaur, but I'm not dead yet.

Tuesday, July 15, 2008

Is 70% Good Enough?

This is a patient conversation that I have had on many occasions:

Patient: I hear there’s this new vaccine available. Can you tell me about it?

Me: Sure. After a primary series of three shots, it provides 70% protection.

P: That’s it? I have a 70% less chance of getting the disease?

M: That’s right.

P: Does it mean I don’t have to worry as much about watching for it?

M: No. It doesn’t change the recommendations for surveillance at all. You still have to do the same things to screen for the disease.

P: Is the disease dangerous?

M: Well, if you let it go for a long time without doing anything about it, yes, it can be very dangerous. But if you catch it early, as it almost always is, it’s quite easy to treat. Treatment isn’t a picnic, of course; there are side effects with all treatments. But it’s completely curable if caught early.

P: Are there any other things I can do -- besides getting the shots -- to decrease my chances of getting the disease?

M: Absolutely! There are several recommendations.

P: So let me get this straight: after three expensive, painful shots, I still have to do regular screenings for the disease, which can be completely cured if treated early, and there are other ways to lessen my chances of getting it in the first place?

M: Yep.

P: Hm.

I’ll bet you all thought this was the discussion about the pros and cons of the new HPV vaccine Gardasil. Well, it is, but it’s also the EXACT same conversation about a vaccine few people remember anymore: LymeRx, the vaccine for Lyme disease sold by (then) SmithKlineBeecham. From April of 1999 through the end of 2001, I gave out 40 doses of it. Here’s my timeline:

4/99 - 12/99: 25
All of 2000: 12
All of 2001: 3

I live in an endemic area for Lyme disease. I see it and diagnose it frequently, before, during and after the time I was vaccinating against it. So what happened? SmithKline couldn't make any money on it, because whenever I had the above conversation with my patients, it usually ended with the patient saying this:

“Given what you’ve just told me about the shot and the disease, I don’t think it’s worth it.”
Despite the abuse we usually heap on patients’ intelligence by complaining about how stupid they are, I think many of them are remarkably resistant to the marketing efforts of the vaccine manufacturers. They read, watch and listen, but then they come in and ask us doctors for our opinion. When couched in the terms above, it turns out -- historically -- that 70% wasn’t good enough for them; at least not for Lyme disease.

The calculation for Gardasil and HPV is remarkably similar. Once you sit down and explain the relationship between HPV infection and cervical cancer, much of the Gardasil marketing loses its punch; not because cervical cancer isn’t scary enough, but because its actual prevalence in this country doesn’t justify the hype. (Using global HPV incidence and prevalence figures to scare American consumers is like trying to get a kid to finish his dinner by telling him there are starving children in Africa. They’re very quick to pick up on the absence of logic in that one.) It's so much less sexy to try to sell HPV immunization as "Reduces your chance of an abnormal pap by 70%." My experience with the Lyme vaccine leads me to believe that Gardasil will probably suffer a similar fate eventually.

So there you have my take on Gardasil. Present patients with the options and let them decide for themselves if 70% is good enough.


At Tue Jul 15, 08:12:00 PM, Blogger Amanda said...

not in my estimation.

At Tue Jul 15, 09:37:00 PM, Blogger Midwife with a Knife said...

I feel the same way. I think that the primary benefit for Gardasil is in patient populations where pap smears aren't available. Those places (i.e. rural subsaharran africa, for example) are places where Gardasil isn't available anyway, or at least they're places where people who can't get pap smears probably can't get or afford Gardasil. In the US, other than possibly (although certainly not proven yet) decreasing the likelihood of a LLETZ (which can have serious consequences, among them are preterm delivery), the benefit of Gardasil is pretty limited.

At Tue Jul 15, 11:18:00 PM, Blogger TBTAM said...

Totally agree. Gardasil is the biggest misappropriation of health care dollars since abstinence only funding. Until we have a vaccine that is effective against all the known HPV subtypes, it's just not worth it. In a few years we will have that better vaccine, and then what? DO we line everyone up again at over $500 a pop?

At Wed Jul 16, 12:14:00 AM, Anonymous Anonymous said...

Well, the US is the first stepping stone with the WHO's vaccine "price teiring" system for new vaccines. So for Gardasil (or rotateq, etc)to be affordable to the two thirds world, it must be mandated here first.

My big problem with Gardasil is that it might not end up being effective.

From an editorial about the FUTURE II trial (which was designed to and powered to detect an effect on cervical cancer)

"In the larger FUTURE II trial,6 rates of grade 2 or 3 cervical intraepithelial neoplasia or adenocarcinoma in situ were 1.3 in vaccinated women and 1.5 in unvaccinated women, an efficacy of 17%. In analyses by lesion type, the efficacy appears to be significant only for grade 2 cervical intraepithelial neoplasia; no efficacy was demonstrable for grade 3 cervical intraepithelial neoplasia or adenocarcinoma in situ. "

"Another factor explaining the modest efficacy of the vaccine is the role of oncogenic HPV types not included in the vaccine. At least 15 oncogenic HPV types have been identified,4 so targeting only 2 types may not have had a great effect on overall rates of preinvasive lesions. Findings from the FUTURE II trial showed that the contribution of nonvaccine HPV types to overall grade 2 or 3 cervical intraepithelial neoplasia or adenocarcinoma in situ was sizable. In contrast to a plateau in the incidence of disease related to HPV types 16 and 18 among vaccinated women, the overall disease incidence regardless of HPV type continued to increase, raising the possibility that other oncogenic HPV types eventually filled the biologic niche left behind after the elimination of HPV types 16 and 18. An interim analysis of vaccine trial data submitted to the FDA11 showed a disproportionate, but not statistically significant, number of cases of grade 2 or 3 cervical intraepithelial neoplasia related to nonvaccine HPV types among vaccinated women. Updated analyses of data from these ongoing trials will be important to determine the effect of vaccination on rates of preinvasive lesions caused by nonvaccine HPV types"


At Wed Jul 16, 12:26:00 AM, Blogger Mark p.s. said...

Do infants have much sexual intercourse? no. Then wait until they are older. If they have a bad reaction to the vaccine-Gardasil , they have a much lower chance of death/perminate injury when older.
Second thing is (to my laymans knowledge) the immune system can "forget" the correct antibody to virus's and such in 5 and 10 years time.

At Wed Jul 16, 12:37:00 AM, Anonymous Anonymous said...

It isn't given until the preteen years. Although it's very common for infants to be infected with the Gardasil strains:

"Results. During the follow-up period (median duration, 26.2 months), HPV DNA was found to be present in 12%–21% of oral scrape samples and in 4%–15% of genital scrape samples obtained from the infants. Oral HPV infection was acquired by 42% of children, cleared by 11%, and persisted in 10% of the infants, whereas 37% were never infected. The corresponding figures for genital HPV infection were 36%, 14%, 1.5%, and 47%."

At Wed Jul 16, 01:09:00 AM, Blogger Special Sauce said...

If I could have had a 70% less chance to not have to flash my cooch every three months for repeat paps, not to mention the colpos, and have saved a bit of that co-pay money, I'd have done it.

Unfortunately, I was too old, and my naughty bits were too tainted by the time Gardasil came around.

At Wed Jul 16, 01:28:00 AM, Anonymous Anonymous said...

Isn't a 70% chance better than a 0% chance, though, without the vaccine?

At Wed Jul 16, 05:40:00 AM, Blogger Evil Lunch Lady said...

My kid tested positive for HPV, and has a few abnormal cells (further testing in a week). So I asked her, would YOU have had the shot?? She said no. She's read all the info on HPV and stands firm. There you have "One" patients opinion. :)

At Wed Jul 16, 07:39:00 AM, Anonymous Anonymous said...

I would have to agree with "special sauce." The potential decrease in abnormal paps, biopsies, colposcopies will save the health care systems millions. Plus we have already had this discussion with the pneumococcal vaccines, I don't see anyone posting on that topic.

At Wed Jul 16, 10:12:00 AM, Blogger KipEsquire said...

Now you understand why Merck bribed Texas governor Rick Perry to issue an executive order making HPV vaccination compulsory in school-aged girls.

At Wed Jul 16, 11:27:00 AM, Anonymous Anonymous said...

I am in the process of being treated for precancerous cervical cells. I will likely have a complete hysterectomy before the end of the year. I wouldn't wish this crap on anyone.

However...I do not trust Merck to have provided correct, complete and sufficient data about Gardisil. They have a tendency to spin things to their own advantage and to the disadvantage of millions of people. (Vioxx, anyone?)

Is the vaccine okay? Maybe. But I want a lot more evidence, objective studies and time before I decide that for my daughter (we're not at that age yet, thank goodness.)

At Wed Jul 16, 03:55:00 PM, Anonymous Anonymous said...

I would think that there is more to the story than just "precancerous cervical cells" for there to be a complete hysterectomy in your future.

At Wed Jul 16, 08:06:00 PM, Blogger Tony said...

To Anon 12:14,
Your representation of the NEJM article is incomplete and therefore inaccurate.

It states that 93% of the enrollees in FUTURE II were nonvirgins. Girls 11 and 12 y/o were not enrolled.

They state, "One factor is the apparent lack of efficacy among subjects with evidence of previous exposure to HPV types included in the vaccine."

Therefore the efficacy in the target population has not been tested.

I am not a shill for Merck or the vaccine industry, rather I am a simple small town gynecologist.

My personal observation: HPV is endemic among 20 and 30-somethings, with nearly every mother in that age group having a friend or sister with HPV. Many of these women are very interested in saving their daughters from the hardship of biopsies, etc.

It will be interesting to see how this plays out, but I think a significant population will choose to vaccinate their daughters. Personally, I counsel that the efficacy is limited in nonvirgins, and it may not worth the cost regardless of what the FDA and Merck say.

At Wed Jul 16, 08:36:00 PM, Blogger The Hatchling said...

This comment has been removed by the author.

At Wed Jul 16, 08:41:00 PM, Blogger The Hatchling said...

One of the things being ignored is that we live in a changing climate and we're talking about an anti-viral vaccine (being touted as an anti-cancer vaccine). Now even if this vaccine works perfectly and blocks the 4 'high risk' strains out of 60+ strains in 5 years the prevalence could easily shift and there would be new and different high risk strains. Thats why we get a new flu vaccine every year, genetic drift. All this will do in the long run is SELECT a different dominant strain that the vaccine doesn't prevent.

Let alone the fact that administration of the vaccine would not change surveillance or screening at all. All I've learned over the past 2 years of medical school is don't do anything that doesn't change outcome.

I'm writing this without looking up the mutagenicity rates of HPV but since it causes cancer I'm assuming its high enough that my point is valid.

As for tony's comments I kind of agree with him about the efficacy in nonvirgins, but based on the trends of American sexuality you need to redefine "virgin" and decide how to convince and 8-12 year olds parents that she needs a vaccine for a STD when we hope she's not having non-Clintonian 'sexual relations.'

Bottom line, people will buy what Merck can hype and sell which is why they're looking to giving the vaccine to guys too. The flaw in the logic is that if pharmaceuticals evolved as fast as bacteria and viruses, we wouldn't be having this discussion at all.


At Fri Jul 18, 10:05:00 AM, Anonymous Anonymous said...

Anonymous said...
I would think that there is more to the story than just "precancerous cervical cells" for there to be a complete hysterectomy in your future.

Wed Jul 16, 03:55:00 PM

You are correct. I was trying not to bore you with the details.

I have undergone numerous colposcopies and LEEP procedures for abnormal precancerous cells. Supposedly after each LEEP there is a small chance of recurrence. I forget the actual numbers at his moment, but well less than 20%. Yet I keep having recurrences. So I am to the point of voting to have the entire works yanked instead of going through this PITA treatment again and again and again and again. My bank account isn't too thrilled either.

My point being, even with all of that, I am still extremely leary of the Gardisil vaccine and would not, at this time with the information I have, have my daughter vaccinated with it.

At Sat Jul 19, 08:41:00 PM, Anonymous Anonymous said...

So here's what I don't get. Why don't we give this vaccine to men as well? They don't have the direct benefit of decreased cervical cancer, but the decreased transmission of disease to sexual partners should, one would hope, provide some incentive.

At Wed Jul 30, 02:26:00 PM, Anonymous Catherine said...

Merck is working on getting the vaccine available to men and older women.

I think the contrary. 70 percent is a good percentage. Why not do it? Its covered by most insurance and its not a big hassle...

Why not just in case?
Pure-ll (spelling) is only 99% effective in fighting germs and people still get common sicknesses even if they use it frequently.. but why do people still buy it? jUST IN CASE.


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