Are there currently any experimental therapies being researched for patients who have already developed symptoms?

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Answer: Okay, regarding this question, let's talk about it.

Conclusion First: Yes, but it's extremely difficult, and there is currently no widely accepted successful cure.

Simply put, scientists have been working hard, but conquering "symptomatic rabies" is one of the most formidable challenges in medicine. Once a patient shows symptoms of rabies (like hydrophobia, aerophobia, throat spasms), the virus has already entered the brain and central nervous system. At this stage, treatment becomes a daunting task.

We can understand this from the following aspects:

Why is it so hard to treat? – The "Blood-Brain Barrier" Hurdle

Imagine our brain as a highly secure "central command center." To protect it from harmful substances in the blood, the brain has a remarkable security system called the blood-brain barrier.

Normally: This barrier blocks viruses, bacteria, and many drugs, ensuring brain safety.
During Rabies Onset: The rabies virus is a master of disguise, able to "sneak" past this barrier into the brain to cause havoc. The critical problem is that the "reinforcements" we use to fight the virus (like antibodies and most drugs) are blocked by this very barrier and kept out.

Therefore, the core challenge of treatment is: How to safely "deliver" effective drugs or antibodies into the brain to precisely target the virus while avoiding excessive damage to the brain itself.

Past Attempts and Current Research Directions

1. The Former Hope: Milwaukee Protocol

You might have come across some case reports online about "curing" rabies; the most famous is the "Milwaukee Protocol."

What is it?: This approach was first attempted by US doctors in 2004. Essentially, it involves placing the patient into an "artificial coma" to minimize brain activity, reducing the damage caused by the virus. Simultaneously, high doses of antiviral drugs and supportive care are used, hoping to buy time for the patient's own immune system to slowly produce enough antibodies to clear the virus.
How did it turn out?: Initially, one unvaccinated patient was saved, which caused a huge sensation at the time. Unfortunately, subsequent attempts globally to replicate this protocol dozens of times resulted in failure in the vast majority of cases. The survival rate was extremely low, and survivors often suffered severe neurological sequelae.
Current Status: Due to its very low success rate and high uncertainty, this protocol is no longer recommended by the World Health Organization (WHO) and mainstream medical communities.

2. Currently Explored New Directions

Scientists have not given up. Current research focuses on more "precisely targeted" methods:

A. Novel Monoclonal Antibodies
- Think of them as "upgraded precision-guided missiles." The rabies immunoglobulin we typically administer is a mixture of antibodies and struggles to cross the blood-brain barrier. Scientists are developing monoclonal antibodies designed to specifically bind to the rabies virus and incorporate special features to make them more adept at "penetrating" the brain. This is one of the most promising areas, with some experimental antibodies already in preclinical or early clinical trials.
B. Novel Antiviral Drugs
- Researchers are screening and developing small-molecule drugs capable of effectively inhibiting rabies virus replication inside nerve cells. This is like searching for the right key to precisely "lock" the virus's replication machinery. There are also candidate drugs under investigation in this area, but clinical application is still a long way off.
C. Combination Therapy (Cocktail Therapy)
- As with HIV treatment, a single approach might have limited effectiveness. The future likely lies in "combination therapy," such as: Novel Monoclonal Antibodies + Novel Antiviral Drugs + Neuroprotective Agents. One set tackles the virus clearance using antibodies and antivirals, while the other uses drugs to protect brain nerve cells and minimize damage.

To Summarize

Yes, experimental therapies are under investigation, particularly focusing on novel antibodies and antiviral drugs.
However, no single therapy has yet been proven to be reliably effective. Once symptoms appear, rabies mortality remains nearly 100%.
Treating symptomatic patients is a constantly evolving scientific frontier. True breakthroughs will require more time and research.

Therefore, regarding rabies, the most crucial thing for ordinary people to remember is always: Prevention is infinitely more important than treatment!

Timely and proper Post-Exposure Prophylaxis (PEP) (wound washing, vaccination, administration of immunoglobulin if necessary) remains the only reliable life-saving method.
Practice responsible pet ownership, vaccinate your pets, and reduce risks at the source.