All interferons interfere with viral replication but until the Cubans show that their drug
Interferon alpha 2B is any better than anything else, then there's nothing to recommend it over anything else used in the treatment of COVID-19.
The list of drugs recommended by CPAM are:
For direct antiviral treatment of SARS-CoV-2, CPAM recommends use
of lopinavir; ritonavir [2 capsule (dose undefined) by mouth twice daily] in combination with nebulized alfa-interferon (5 million units in Sterile Water for Injection inhaled twice daily). CPAM ( China International Exchange and Promotive
Association for Medical and Health Care) has based this recommendation on weak evidence from retrospective cohort, historically controlled studies, case reports, and case series that suggest clinical benefit of lopinavir; ritonavir in the treatment of other
coronavirus infection [i.e., 2002 SARS-CoV and 2012 Middle East respiratory syndrome coronavirus
(MERS-CoV)]. (4) (8) (7)
In addition to CPAM, a group of Korean physicians with experience in treating SARS-CoV-2 infected
patients have developed recommendations for the treatment of COVID-19. According to these
physicians, antiviral medications are not recommended for use in young, healthy patients with mild
symptoms and no underlying comorbid conditions. However, treatment with lopinavir 400 mg; ritonavir
100 mg (2 tablets by mouth twice daily) or chloroquine (500 mg by mouth twice daily) should be
considered for use in older patients or patients with under underlying conditions and serious symptoms.
If chloroquine is unavailable, they recommend considering use of hydroxychloroquine (400 mg by mouth
once daily). Use of ribavirin and interferon were not recommended as first-line treatments because of
the risk for side effects; however, use of these medications may be considered if treatment with
lopinavir; ritonavir, chloroquine, or hydroxychloroquine are ineffective. (12) (13)
It is unclear if the alpha interferon used in China is the same as the one the Cubans are selling.