Yet other researchers are focusing on how these 29 proteins interact with parts of the human cell—with the goal of finding drugs that target the host instead of the virus. While this seems indirect, it follows with the replication cycle of viruses. Unlike bacteria, viruses cannot copy themselves. “Viruses use the machinery of the host,” says Adolfo García-Sastre, a microbiologist at the Icahn School of Medicine at Mount Sinai. They trick host cells into copying their viral genomes and making their viral proteins.

Read: Why the coronavirus has been so successful

One idea is to stop these virus-ordered functions without interfering with a cell’s normal functions. Here, the best analogy for a potential SARS-CoV-2 drug may not be an antibiotic, which kills foreign bacterial cells rather indiscriminately. “I think it’s much more like a cancer therapy,” Kevan Shokat, a pharmacologist at UC San Francisco, told me. In other words, it may be about selectively killing the human cells that have gone haywire. This opens up the possibility of many more drug targets in the host, but it also adds a challenge: It is much easier for a drug to distinguish between human and bacteria than between human and virus-hijacked human.

Antivirals are thus rarely “miracle cures” the way antibiotics can be against bacteria. Tamiflu, for instance, can shorten the duration of the flu by a day or two, but does not outright cure it. Antivirals for HIV and hepatitis C have to be taken in cocktails of two or three drugs at a time because the viruses can quickly mutate to become resistant. The good news about SARS-CoV-2, at least, is that it does not seem to mutate especially quickly for a virus. A number of different steps in the disease cycle could be lasting targets for a treatment.

Stop the virus from getting into a cell

Let’s begin where the virus starts, which is by tricking its way into a host. SARS-CoV-2 is covered in lollipop-shaped “spike” proteins, whose tips can bind to a receptor found in some human cells called ACE2. These spikes are what give coronaviruses—the group of related viruses that includes SARS-CoV-2 as well MERS and SARS—their name, because they create a crown- or corona-like appearance. The three coronaviruses are similar enough in their spike proteins that scientists are repurposing strategies from SARS and MERS to fight SARS-CoV-2. The vaccine from Moderna, for example, was able to start clinical trials so quickly in March because it is based on previous research into MERS’s spike protein.

The spike protein is also the focus of antibody therapy, which is likely faster to create than a new pill because it harnesses the power of the human immune system. The immune system makes proteins called antibodies to neutralize foreign proteins, such as those from a virus. Several hospitals around the country are trying to infuse antibody-rich plasma from COVID-19 survivors into patients. Currently, research groups as well as biotech companies are also screening the survivor plasma to identity antibodies that can be manufactured en masse in a factory. Spike proteins are a logical target for antibodies because the proteins are so plentiful on the outside of the virus. And again, the similarities between SARS-CoV-2 and SARS helps. “It looked enough like SARS that we had a bit of a head start,” says Amy Jenkins, a program manager at the Defense Advanced Research Projects Agency, the Pentagon’s blue-sky research arm, which is funding four different groups working on antibody therapy against the new virus.