1/n Where's the vaccine already? A summary of the current state of research into a vaccine for the coronavirus (SARS-CoV-2) with a bunch of digressions thrown in. If you've been following the news, you probably know most of this.

2/n All vaccines rely on triggering the body's immune response to fight an infection. Historically, this has involved using a weakened virus. In fact, the word vaccine comes from the latin word vacca (cow) from the early use of the cowpox virus (vaccinia) against smallpox.

3/n More novel methods are also being explored. ~80 groups around the world are researching a vaccine, with some now entering clinical trials.

4/n Moderna, a smallish US-based pharma company is working on an mRNA based vaccine. The corona virus has spike proteins on its surface, which is how it invades your cells. (These proteins assemble into "trimers" resembling a crown, which is what gives the virus its name).

5/n In an mRNA based vaccine, laboratory developed mRNA (messenger RNA) is introduced into your cells. Moderna's mRNA instructs your cells to produce spike proteins. The body's defence mechanisms kick in and create antibodies to protect against the protein.

6/n These antibodies can also then protect you if you're ever infected by the virus.
The company has seen encouraging results in Phase 1 trials. (The vaccine will have to undergo four phases of trials before it can be approved for human use at scale).

7/n Inovio, a US-based company is working on a DNA vaccine. Introducing foreign DNA into a cell is challenging. Inovio's technology involves using electroporation, which is the application of electrical pulses to create pores in the cell membrane through which DNA is injected.

8/n The reason these approaches are exciting is that mRNA and DNA vaccines do not cause disease, which means they can be widely administered, including to immuno-compromised individuals.

9/n Sinovac Biotech, a Chinese company has taken a more traditional approach to developing a vaccine, whereby a chemically inactivated version virus is used. This has been shown to be effective in monkeys.
Some interesting info about Sinovac at the end of this thread.

10/n Pharma giants Sanofi and GSK have partnered to develop a vaccine.

11/n The Oxford Vaccine Group has been working on a vaccine (ChAdOx1 nCoV-19 vaccine) which triggers an immune response using a "safe" virus. A safe virus is created by injecting segments of corona code into a harmless virus that infects chimpanzees.

12/n The vaccine has shown promising results in rhesus monkeys. Oxford has inked a deal with AstraZeneca, a large pharma company headquartered in the UK for distribution.

13/n The Serum Institute in Pune, India (the world'a largest vaccine manufacturer) is scheduled to start production of the vaccine developed by Oxford before the full completion of trials, so sufficient quantities of the vaccine are available if clinical trials are successful.

14/n They're also partnering with US-based biotech firm Codagenix on a live-attenuated vaccine.

15/n The ICMR (Indian Council of Medical Research, the apex body for biomedical research in India) is collaborating with Hyderabad-based Bharat Biotech who will be researching the use of an attenuated virus vaccine.

16/n Bharat Biotech has also partnered with the University of Wisconsin, Madison, and the US-based company FluGen to develop a nasal vaccine CoroFlu built on an existing flu vaccine (M2SR) which contains the weakened live H3N2 influenza virus.

17/n Ahmedabad-based Zydus group (which was the first to develop and indigenously manufacture a Swine Flu vaccine in 2010), is developing a COVID-19 vaccine through its research arm in Europe, Etna Biotech.

18/n Smaller Indian companies such as Gurugram-based Premas Biotech, Ahmedabad-based Hester Biosciences and start-ups Neuberg Supratech and Mynvax are also in the fray. Aside: 70% of the world's vaccines are made in India. :O

19/n Certain existing drugs such as chloroquine / hydroxychloroquine (antimalarial), remdesivir (originally developed to combat Ebola) and ritonavir / lopinavir (used to treat HIV) are also being studied.

20/n Incidentally, Moderna has been in the news recently because as an early player in the vaccine development race, the company has seen their share price jump ~250% since January.

21/n They sold $1.3 billion worth of stock on the day they announced the results of their Phase 1 trials (when the share price gained 20% in a single day) to fund production of the vaccine.

22/n On the other hand, thanks to a year long corporate battle, Sinovac (SVA) hasn't been able to tap into the public markets to fund its R&D efforts. Instead, it has raised $15 million through convertible debt from two private investors.

23/n Aside: Convertible debt is a loan that pays a regular interest rate (coupon) to the investor but can later be converted to equity (a certain number of shares).

24/n This is because in February 2019, Nasdaq halted trading on SVA stock. Why? In 2018, a group of investors (over the course of many months), stormed their offices, and attempted to replace their board.

25/n SVA alleged that hedge fund 1Globe and other investors had colluded to stage a coup. In response, SVA triggered their "poison pill" which allows them to issue new shares to investors that did not participate in the coup thus diluting the shareholding of those who did.