Health Newsfeed – Johns Hopkins Medicine Podcasts

Anchor lead: The Covid Astra Zeneca vaccine is being used in the UK and elsewhere, Elizabeth Tracey reports

Even as vaccines against Sars-CoV2 in the US use technology known as mRNA, elsewhere in the world another type of vaccine using a virus known as an adenovirus is also being used. Andrew Pekosz, a vaccine expert at Johns Hopkins, explains some differences.

Pekosz: Adenovaccines have a longer history of use. Adenovirus vaccines are almost on the complete other end of the spectrum when it comes to stability when you compare them to mRNA vaccines. They can be stored at room temperature. They can be stored in a fridge for extremely long periods of time without any kind of degradation. The advantage that they give now is especially important when it comes to places like Africa, various parts of southeast Asia, places where cold chains are virtually impossible to keep.  :29

This adenovirus vaccine was developed by Oxford University and the pharmaceutical company AstraZeneca, and has also been in clinical trials here in the US, where it’s makers will likely seek authorization or approval soon.[RC1]  At Johns Hopkins, I’m Elizabeth Tracey.

Anchor lead: Why do the Covid vaccines currently being used require two doses? Elizabeth Tracey reports

Most vaccines we’re accustomed to require a single injection, with a booster several years or even decades later. Why do the Covid vaccines currently in use require two doses? Andrew Pekosz, a vaccine expert at Johns Hopkins, explains.

Pekosz: With coronaviruses we have no immunity, so the first time your body sees this antigen, it recognizes it as foreign, but it doesn’t really go to the nth degree in terms of making antibody responses. It makes some, and actually this vaccine makes a significant amount, but it’s really the second time you see the antigen that your body now says, all right, this is foreign, and I’m seeing it again. Now this is really a threat so now I’m going to increase the amount of antibodies that I’m making and really generate a large strong amount of antibodies.  :30

Pekosz says most childhood vaccines do require a couple of doses, and the flu vaccine requires a single dose yearly because most of us have had some previous exposure to influenza. At Johns Hopkins, I’m Elizabeth Tracey.

Anchor lead: When you get the Sars-CoV2 vaccine, what should you expect? Elizabeth Tracey reports

Are the vaccines currently in use against Sars-CoV2 associated with more side effects than other types of vaccines? Andrew Pekosz, a vaccine expert at Johns Hopkins, explains.

Pekosz: If you compare it to the flu vaccine it seems to be a little bit more, we use the technical term ‘reactogenic.’ What that means is you’re a little bit more sore at the site of injection, a few hours later or a day later. You can get a little bit of redness and tenderness in that area, for a couple days. Some people have spiked a fever, but compared to the placebo group, those changes are significant but not to an overly concerning level. So it’s really just the symptoms that we often attribute to your immune system actually kicking in and doing its job.   :31

The most recent data from the federal Vaccine Adverse Events Reporting System or VAERS does not find a large number of severe reactions among the 3 million or so people who have received the vaccines in the US. At Johns Hopkins, I’m Elizabeth Tracey.

Anchor lead: mRNA technology has been under development for use in vaccines for quite some time now, Elizabeth Tracey reports

What makes an mRNA platform, currently in use in both Sars-CoV2 vaccines being administered in the US, so attractive? Andrew Pekosz, a vaccine expert at Johns Hopkins, says abundant research experience utilizing this technology for a variety of infectious diseases enabled researchers to move quickly.

Pekosz: People say that they’re a little bit concerned about this being a new platform but we should point out that there have been an awful lot of phase 1 clinical trials using mRNA vaccines for a host of different emerging infectious diseases. So there’s actually a good base of clinical studies that were used to guide everything that happened this year with the Covid-19 mRNA vaccines.  :23

Pekosz believes many types of vaccines, most especially the flu vaccine, will soon be made using this platform, which may enable the development of a flu vaccine that would only have to be administered once every few years rather than yearly as we do now. He is also confident that if a new strain of Sars-CoV2 emerges a vaccine can be developed fast using mRNA technology. At Johns Hopkins, I’m Elizabeth Tracey.

Anchor lead: What makes the mRNA vaccine so effective? Elizabeth Tracey reports

With a name like Operation Warp Speed, it’s no wonder people may be feeling that the vaccines currently being used against Sars-CoV2 have been rushed into distribution. Andrew Pekosz, a vaccine expert at Johns Hopkins, says these types of vaccines have been under development for more than two decades.

Pekosz: The mRNA vaccine platform is tailor-made for a disease like coronaviruses, where we’re expecting that antibody responses to the outer proteins are going to be able to drive the vast majority of protection from disease. That’s because these mRNA vaccines are designed to do just that; to take a protein and just express a lot of it on the surface of a cell. That then leads to a nice recognition of hey, this is a foreign item and your immune response kicks right in.  :29

Pekosz predicts that many other infectious diseases will soon have vaccines against them using this same technology, and that the need to keep such vaccines extremely cold will also be overcome, making them much easier to administer. At Johns Hopkins, I’m Elizabeth Tracey.

Anchor lead: There’s good news for people with one type of lung cancer, Elizabeth Tracey reports

If you have non-small cell lung cancer with a receptor called EGFR, you are likely to respond to an agent called osimertinib, a new study finds. William Nelson, director of the Kimmel Cancer Center at Johns Hopkins, is excited.

Nelson: You can’t make this into anything but good news. Osimertinib is an inhibitor of this mutant epidermal growth factor receptor, EGFR, signaling system. This is an on/off switch and its stuck in the on position driving lung cancer cells to grow, so can you force it back off with a drug that’s the idea of this drug Osimertinib.  :20

Nelson says this agent is the latest of a group targeting this receptor.

Nelson: It’s the setting where these drugs and there are several of them right now might antagonize this on switch by forcing it in the off position.  :07

Nelson says the advantage to Osimertinib is it is able to penetrate the brain and spinal cord, and that’s helpful for mopping up cancer cells throughout the body. At Johns Hopkins, I’m Elizabeth Tracey.

Anchor lead: How does a global study of cancer inform public health? Elizabeth Tracey reports

Cancer diagnoses are up worldwide, by about a third, the Global Burden of Disease study finds. William Nelson, director of the Kimmel Cancer Center at Johns Hopkins, says there are big differences between countries on which cancers predominate.

Nelson: In the countries that have higher sociodemographic development and indices, they’ve been deploying screening, early detection, and if anything we’ve taken a while to get up to overdiagnosis and overtreatment- are we detecting cancers that aren’t very threatening, do we manage them correctly? So we’re on I think a good trajectory in the better developed counties, I think tragically what we’re seeing in the lesser developed countries is that you’re still seeing cancers that are uncommon in the developed countries. It tells you what you need to do to get those countries better off.    :30’

Nelson is confident that what he calls ‘legacy cancers’ such as cervical and liver cancer will be gotten under control soon worldwide. At Johns Hopkins, I’m Elizabeth Tracey.

Anchor lead: What does a new global analysis of cancer cases tell us? Elizabeth Tracey reports

The latest Global Burden of Disease study tabulates different types of cancer experienced by people worldwide, and shows a rather dramatic increase in cancer incidence overall. That’s according to William Nelson, director of the Kimmel Cancer Center at Johns Hopkins.

Nelson: In 2017 24 and a half million new cancer cases, 16.8 million were those we don’t count – non-melanoma skin cancers, the basal cell and squamous cell cancers, 17 million more or less serious cancers, 9.6 million deaths, and they estimate 223.5 million disability adjusted life years, that accounts for feeling sick or being treated so that you’re not engaged in your life more fully. Cases increased by 33% and so cancer is on the rise.  :33

Nelson says some of the rise is due to better detection and imaging methods but notes that cancer risk increases with advancing age also, so as more of us live longer some of us will develop cancer. At Johns Hopkins, I’m Elizabeth Tracey.

Anchor lead: Black men with low risk prostate cancer need active follow-up, Elizabeth Tracey reports

Many men with prostate cancer are categorized as low risk, meaning that they can be safely watched over time, and if the disease progresses treatment may then be employed, without a compromise of safety. Now a new study establishes that approach for Black men, who have historically had worse outcomes. William Nelson, director of the Kimmel Cancer Center at Johns Hopkins, describes the results.

Nelson: This confirms the suspicion that African American men may be at slightly increased risk to sprout a more aggressive cancer and need more treatment so they need to be watched. The active surveillance needs to be active, but it was also very safe to deploy this kind of strategy for African American men, as safe as it was for European men.  :17

Nelson says disparities may be the result of when the disease is diagnosed.

Nelson: The bias that leads to increased mortality among African Americans is many of them when they’re first diagnosed have more aggressive prostate cancer.  :08

At Johns Hopkins, I’m Elizabeth Tracey.

Anchor lead: Do different ethnic groups have different risks for prostate cancer to recur? Elizabeth Tracey reports

When Black and Caucasian men develop low risk prostate cancer, does active surveillance yield equal risk for progression? William Nelson, director of the Kimmel Cancer Center at Johns Hopkins, says Black men in this large VA study did indeed develop more aggressive disease more often.

Nelson: They had a significantly increased chance that the disease would sprout something more aggressive. So about 59% versus 48.3% would need some more aggressive treatment. They did not find any difference in the propensity to develop metastatic disease; it was incredibly low. One and a half percent basically. It was very safe to do this, but African American men had a slightly higher chance to perhaps need more aggressive treatment at some point in the future.  :31

Nelson says this study confirms the safety of this approach for men of different ethnicities, and notes it underscores the need to be vigilant for signs of accelerating prostate cancer. At Johns Hopkins, I’m Elizabeth Tracey.