SANTIAGO — Imagine a Mexican-style lucha libre wrestling match between pharmaceutical products. On one side is Kikuzubam, the molecule of the poor. His flashy challenger is Rituximab, produced by a wealthy pharma firm called Roche.

Kikuzubam taunts his rival, telling him he is just as tough. The judge gives him the first round when he says, "no need for clinical tests!"

But the rules change in the second round. The judge now demands testing. Kikuzubam starts feeling the heat. Some in the audience — Kikuzubam's fans in the public health sector who "love him, he's so cheap!" — boo the decision. The knockout blow comes later, when the judge removes Kikuzubam's licence. One, two, three, four ... The champion of the poor is down for the count.

For now, at least, Rituzimab, the fancy Swiss rival, is still king of the ring.

Welcome to the global fight between bio-technology and generics, which have now begun locking horns in the Americas. The prize? A huge and growing market in beating tough diseases.

The chief problem is a lack of rules. States are inclined to buy cheap copies with little certification. Big labs counter by taking their competitors to court. For now, labs, governments and patients are all maneuvering to protect their respective interests.

Until recently, big firms argued that biopharmaceutical products could not be copied. It turns out they were mistaken, and the battle has shifted to the rules governments should impose on copiers, whose products are entering the market as patents written in the past 20 years expire. That is where lobbying comes in — another area short on rules!

What lobbying by the drug firms does is delay discussion and approval of laws to regulate generics, says Juan-Manuel Anaya of the Colombian Rosario University's center for the study of autoimmune diseases. It can take strange forms: when Colombia's ambassador to the U.S., Luis Carlos Villegas, wrote to the Colombian Health Ministry in July 2014 to inform it of U.S. firms' "concerns" over a ministerial decision to regulate generics, the country's lawmakers were indignant. "Was he lobbying for those firms," asked one Colombian senator?

"Take it if it makes you happy"

As Andrés Felipe Cardona, head of the cancer NGO RedLANO, observes, governments also have their agenda, which is always to pay less. "The state doesn't care if the drug works or not. It sees who is charging less. Some countries, like Ecuador and Argentina, are completely lax and let any drug product can come in."

After its knockout last March, Kikuzubam was entirely withdrawn from the market. Roche, in the meantime, looks set to recover its licence. End of story? Not quite. Turns out there is a third player also wanting a piece of the action: Reditux, a generic made by Dr Reddy, an Indian laboratory.

Reditux is available in Ecuador, Peru, Chile and Bolivia. Labs distributing it have already accused Roche of trying a range of tricks to keep the product out of regional markets, in spite of public demand. Looks like the patients themselves are trying to enter the ring!

The lack of debate on biogenerics means that many physicians in Latin America are fuzzy about their qualities. When Laura Parilla had chemotherapy for breast cancer in Mexico City, relatives recommended she take Interferon to mitigate the effects. "I asked a doctor and, with total indifference, he told me "it won't do you any good or harm, take it if it makes you happy,"" she says.

Many doctors "have no idea" about the differences between patented and generic drugs, says Richard Salvatierra, head of the Americas Health Foundation. "Sometimes they change one for the other without the patient knowing." Patients are starting to demand access to generic drugs.

All eyes on Brazil?

This lack of debate is unusual considering how many Latin American leaders have had cancer. The list includes Venezuela's Hugo Chávez, who died in 2013, former Paraguayan President Fernando Lugo, Argentina's Cristina Kirchner and Brazil's Lula da Silva and Dilma Rousseff. After the latter had her lymphatic cancer treated with Rituximab, Brazilian patients went to court to demand it become available in public hospitals. The country is set to start producing its own version, as Rituximab's patent ended two years ago.

While experts see regulation as the solution, after Rousseff's illness, Brazil sought to make drug firms and copiers collaborate.

Brazil is currently the largest market for and biggest producer of generic drugs in Latin America, with government backing. Firms are encouraged to invest in making products whose purchase by public health authorities is increasingly assured, through PDPs or product development partnerships. "It will allow the country to make its own pharmaceutical products in Brazil," says Reginaldo Arcuri of BrasilPharma.

The big labs are observing Brazil even as they too have begun making generics. Their change of outlook is evident in their acceptance of Brazilian state initiatives to boost biogenerics. "It is a global and natural movement," says Vera Valente, head of biogenerics at Merck. "The firm decided to embrace the cause and formed its biosimilars division. If we don't do it, someone else will."

The first set of rules for biogenerics emerged from the European Medicines Agency (EMA) in 2005. The World Health Organization issued its own document in 2010, and American states used such texts to formulate their own regulations. There is no global set of norms for now, nor an oversight body to check products and their effects. In Latin America, generics function mostly under rules applied to patented drugs.

"Ask someone in a country if biosimilars are working and they tell you, "sure, nobody died from them"," says Richard Salvatierra. "But nobody knows their exact benefits."

But with changing perspectives, they are here to stay. When oncologist Jaime de la Garza headed Mexico's National Cancer Institute, he once chose a generic over a patented drug for being half the price. He recalls that a rep from the firm Bristol-Myers Squibb came to tell him the generic he had chosen over their product "is no good." Years later, says de la Garza, the rep was found working "in the firm making the copies and I asked him, why are you working in a firm that makes useless products? He said "the market changed.""

Ring the bell for round three!

*Marlene Jaggi in Sao Paulo and Camilo Olarte in Mexico City contributed to this item.